According to the American Academy of Pediatrics(AAP), exclusive breastfeeding of infants for about the first six months and continued breastfeeding for a year or longer after introducing solid foods is recommended.
The World Health Organization(WHO) also recommends exclusive breastfeeding for the first six months of an infant’s life.
Exclusive breastfeeding refers to giving infants only breast milk and no other solid or liquid foods. According to the Centre for Disease Control and Prevention(CDC), only one in four infants are exclusively breastfed for the first six months.
Breastfeeding is beneficial for both the infant and the mother. Benefits of breastfeeding include:
Research shows that mothers who breastfeed have a lower risk of developing pre and postmenopausal breast cancer. This benefit increases with an increase in the duration of breastfeeding for more than 6 months.
Researchers have put forth several possible explanations to address the link between breastfeeding duration and breast cancer risk. All these explanations revolve around exposure to one of the female sex hormones, estrogen.
Estrogen stimulates breast cell growth. Prolonged exposure to estrogen can increase the risk for breast cancer. Women have lower levels of estrogen during breastfeeding periods. This is because breastfeeding delays menstrual periods. The lifetime exposure to estrogen decreases with longer breastfeeding durations, and this decreases the risk of breast cancer.
Another reason is that the breast sheds a lot of tissue after lactation. During this process, it may also get rid of cells with damaged DNA that may lead to cancerous growth. Lactation may also lead to changes in the expression of genes found in breast cells. This can decrease the risk of cancer development.
A meta-analysis study showed that breastfeeding contributed to a 20% reduced risk for triple-negative breast cancer and a 10% reduced risk for estrogen receptor-negative breast cancer.
Studies have estimated that the heritability of breastfeeding duration ranges from 44 to 54%. People with certain genetic types may tend to breastfeed their children for a longer duration than others.
The XRCC2 gene contains instructions for producing a DNA repair protein. This protein also helps maintain chromosomal stability.
Changes in this gene are associated with increased risk of breast cancer and fanconi anemia. Fanconi anemia is a rare but serious blood disorder that prevents your bone marrow from making enough new blood cells for your body. It is passed down through families.
rs3218536 is a single nucleotide polymorphism or SNP located in the DNA-repair gene XRCC2.
A 2010 study examined the role of DNA repair deficiencies in cancer development, especially in breast cancer. The study population was divided into women who breastfed and women who had never breastfed.
It was observed that among women who had never breastfed, those who carried the AG genotype of rs3218536 had a lower risk of breast cancer than those with the other genotypes.
After classifying this group according to the menopausal status, it was observed that postmenopausal women with the A allele had a lower risk of breast cancer than those with the G allele.
The MDM2 gene contains instructions for the production of Mouse double minute 2 homolog (MDM2) protein. It is also known as E3 ubiquitin-protein ligase Mdm2 protein.
This protein acts as a negative regulator (suppresses the activity) of p53 tumor suppressor protein.
A study has reported that the activity of the MDM2 gene seems to be amplified in breast cancer cells.
rs2279744, also known as 410T-G, has been studied for several years to determine its role in cancer.
This SNP influences the ability of the MDM2 protein to bind to p53 tumor suppressor protein.
The G allele of this SNP is associated with an increased risk for breast cancer, especially in women who have breastfed for less than 6 months and women who are obese.
Some factors that influence breast cancer duration include:
It is important to get periodic breast cancer screening done. Some screening options include mammography and breast MRI. You can check with your medical practitioner for suitable tests.
Prognosis refers to the outlook or chance of recovery from a disease. It is an estimate of the likely course and outcome of a disease - breast cancer, in this case. This includes the likelihood of recurrence and life expectancy.
Breast cancer prognosis is based on observing large groups of people affected by the condition over the years. It can be qualitative and described as excellent, good, or poor. It can also be quantitative in the form of survival rates or hazard ratios.
The survival rate is determined by observing several people affected with breast cancer for many years, usually five or ten years. Survival rates are a key part of cancer prognosis. It indicates the percentage of people alive after a certain period of time, usually five years, after they were diagnosed.
Survival rates can help give you a better understanding of how successful your treatment may be. Two main survival rates used in breast cancer cases include
According to the National Cancer Institute, 90 percent of women with breast cancer survive five years after diagnosis, regardless of the stage. This indicates a 90% five-year survival rate - 90 out of 100 people diagnosed with breast cancer are likely to be alive after five years.
Another parameter used to determine prognosis in cancer patients is the hazard ratio. Hazard ratios are used to measure survival in a group of patients who have been given a specific treatment in a clinical trial setting.
The patient group is compared with the control group, who are given a placebo, a treatment with no therapeutic value.
Hazard ratio can either be equal to, lesser than, or greater than one.
No difference in survival between the two groups receiving different treatment is denoted by a hazard ratio of 1.
A value greater than or lesser than one indicates better survival in one of the treatment groups.
Prognosis in terms of survival rates or hazard ratio is just an estimate based on previous outcomes of large groups of people with specific cancer. Every case is unique, and the survival rate is not a very accurate prediction of a specific person’s prognosis.
The statistics can be confusing and alarming in some cases. Talk to your doctor about these statistics, how they apply in your case, and what you can do about it for better clarity.
The prognosis for breast cancer survivors and their survival depends on many factors. This can be assessed only by a qualified physician familiar with the medical history, response to treatment, type and stage of cancer, and cancer-specific characteristics.
A family history of breast cancer increases the individual’s risk of developing breast cancer. Genetics also influences breast cancer prognosis. Changes in certain genes may be responsible for the considerable differences in survival among breast cancer patients.
The RAD51B gene contains instructions for the production of a protein involved in DNA repair. Along with other proteins of this family, the RAD51B protein is involved in repairing damaged DNA. Changes in this gene can disrupt the DNA repair process and influence breast cancer prognosis.
rs3784099 is a single nucleotide polymorphism or SNP in the RAD51B gene. Carriers of the A allele are found to have lesser survival time and unfavorable prognosis.
Apart from genetic factors, your doctor will consider several other factors to determine prognosis, including:
The statistics, survival rates, and hazard ratio values can be confusing. A doctor familiar with your medical history can help interpret breast cancer prognosis based on genetic and non-genetic factors. Certain ways to improve the prognosis of breast cancer include
Getting sufficient sleep: Breast cancer survivors need about 7 to 9 hours of sleep every night. In a study conducted by researchers from Fred Hutchinson Cancer Research Center, Seattle, women who slept for a period of 5 hours or less every night before being diagnosed with breast cancer had a 1.5 times higher likelihood of poor prognosis when compared with women who slept for 7 to 9 hours every night.
Regular exercise: Regular exercise improves prognosis; however, it might not be possible for everyone to exercise daily during the treatment. According to a study conducted by researchers at The University of California-San Diego Moores Cancer Center, a 12-week exercise program increased information processing speed by 2 times. This indicates cognitive benefits of exercise; however, the benefit is obtained only when the exercise program starts within 2 years of being diagnosed with breast cancer.
Alternate or Complementary Therapy: In North America, nearly 80% of breast cancer survivors depend on complementary therapy to cope with breast cancer. The most sought-after therapy is yoga.
Yoga has been shown to reduce fatigue, improve sleep quality, physical functioning, and overall quality of life.
Lifestyle: Try to moderate or avoid smoking and alcohol consumption as these are risk factors for many types of cancer and may result in an unfavorable prognosis. Eat a healthy and balanced diet to maintain a healthy weight.
Receptors are proteins inside the target cell or on its surface that receive a chemical signal.
Estrogen is an important hormone responsible for various female characteristics in the body, including the growth and development of breasts (or mammary glands).
Estrogen Receptors (ERs) are a type of steroid receptors that attach to estrogen in the blood and regulate the growth and multiplication of cells in the breast. These receptors pick up signals from the hormones and encourage cell growth.
In the case of breast cancer, this growth is uncontrollable and eventually becomes cancerous.
Based on the presence or absence of estrogen receptors in breast cancer cells, there are two types of breast cancers:
A cancer is called estrogen-receptor-positive (or ER-positive) if it has receptors for estrogen. The cancer cells receive signals from estrogen and grow in response to it.
ER-positive is the most common form of breast cancer - around 80% of breast cancers are ER-positive.
Anti-estrogen medications can prevent the growth of these cancer cells.
Breast cancer cells that do not have estrogen receptors are known as estrogen-receptor-negative (or ER-negative) cancers.
ER-negative breast cancer is less common and more challenging to treat. It also often has poor treatment outcomes.
Knowing whether breast cancer is ER-positive or ER-negative helps doctors plan the appropriate treatment.
Every patient with a breast cancer diagnosis undergoes a hormone receptor evaluation that helps determine if the cancer cells have receptors for estrogen and progesterone.
Testing breast cancer cells for hormone receptors is important to decide whether hormonal therapy will be an effective course of treatment.
Hormone therapy involves reducing the estrogen levels in the body or blocking the cells from responding to estrogen.
Only if the cancer is ER-positive, hormone therapy will work.
This makes ER-negative cancers difficult to treat; non-hormonal treatments are used for these cancers.
The BRCA2 gene provides instructions for producing a protein that acts as a tumor suppressor (proteins that prevent cells from dividing uncontrollably and rapidly).
The BRCA2 gene is also involved in repairing damaged DNA.
Changes in the BRCA2 gene can increase the risk of different types of cancers, including breast cancer.
Most women with BRCA2 mutations tend to develop ER-positive breast cancer. However, the prognosis may be worse for these women than for those with ER-negative breast cancer carrying BRCA2 mutations.
The MDM4 gene is located on chromosome 1 and produces the MDM4 protein, which regulates a tumor suppressor protein called the p53.
Changes in this gene can affect the protein produced, which in turn interferes with the tumor suppressor activity of p53.
When this happens, it can lead to uncontrolled cell growth resulting in cancer cell formation.
The ZNF365 gene contains instructions to produce the Zinc Finger Protein 365. This protein plays a role in repairing DNA damage. Changes in this gene increase the risk of breast cancer.
A change in the ZNF365 gene, called 19p13.1, has been linked to ER-negative breast cancer in individuals with changes in their BRCA1 and BRCA2 genes.
Race: There is a higher incidence of ER-negative breast cancers in women of African ancestry.
Obesity: Pre-menopausal and menopausal women who are overweight or obese are at an increased risk of developing ER-negative breast cancer.
Alcohol consumption: Increased alcohol intake increases the risk of ER-negative breast cancer.
Younger Age: Hormone receptor-negative cancer is more commonly seen in women around 40 years of age who haven’t attained menopause
Physically active women who have a healthy weight and lead a healthy lifestyle have a reduced risk of developing ER-negative breast cancer.
Even low levels of alcohol intake can increase the risk of breast cancer. The ideal upper limit for alcohol consumption to lower breast cancer risk is one drink a day (12-14 grams of alcohol).
Plant-based diets are packed with fiber, vitamins, and minerals. Fiber helps eliminate excess estrogen (a risk factor for breast cancer). Vitamin C, A, and selenium also play a role in lowering cancer risk.
A 2013 study that followed approximately 30,000 post-menopausal women with no history of breast cancer for 7 years showed that following these three recommendations resulted in a 62% decreased risk of breast cancer.
The BRCA genetic test is a blood test that analyses DNA to detect the presence of harmful changes (mutations) in the BRCA1 and BRCA2 genes. Individuals with these mutations are at a high risk of developing breast cancer. Routine testing for these genes in individuals at high risk is recommended.
Breast cancer is one of the most common types of cancer affecting women. According to the World Health Organization (WHO), 2.3 million women were diagnosed with breast cancer, and 685,000 lost their lives globally in 2020.
As of 2020, 7.8 million women have been diagnosed with breast cancer and are alive in the last five years.
Breast cancer survivors are at risk for different health conditions - fatigue, mental health issues, and breast cancer recurrence - to name a few. They must also be aware of the higher risk they carry for developing a second non-breast cancer.
People who have had breast cancer in the past are at higher risk for developing other types of cancers, including:
A 2006 study collected data from 13 different cancer registries in places like Singapore, Canada, Australia, and Europe. The study analyzed the data of 525,527 women and followed them for 10+ years.
According to the study, when compared to women who did not have a history of breast cancer, women with past or present breast cancer had:
Another study analyzed the risk of Secondary Non Breast Cancers (SNBCs) in 58,068 Dutch women diagnosed with breast cancer between 1989 and 2003. According to the study, women who had breast cancer in the past had a small but significant risk for developing esophageal cancer, stomach cancer, colon cancer, rectum cancer, uterus cancer, ovarian cancer, soft tissue sarcoma, acute myeloid leukemia (AML), and non-Hodgkin’s lymphoma.
The BRCA1 gene (BRCA1, DNA repair associated gene) produces a tumor suppressor protein. This protein is considered beneficial as it hinders uncontrolled cell division, thereby lowering cancer risk.
Abnormal changes (or variations) in this gene can lead to low or no production of the tumor suppressor protein and increase one’s risk for developing cancers.
A study reported that BRCA1 variations lead to breast and ovarian cancers and also increase the risk of other cancers like colon cancer (11.1%), pancreatic cancer (3.6%), and gastric cancer (5.5%).
The BRIP1 gene (BRCA1 interacting protein C-terminal helicase 1) contains instructions for producing a protein that repairs double-strand breaks in DNA.
Abnormal changes in this gene result in lower production of this protein, which increases the risk of many types of cancers. Cancers associated with variations in this gene are:
The PALB2 gene (Partner And Localizer Of BRCA2 gene) contains instructions for producing a protein that works with the BRCA2 protein to repair damaged DNA and suppress tumor growth. Abnormal changes in this gene affect the ability of the BRCA2 gene to prevent tumor cell formation.
Apart from breast cancer, this gene is associated with the risk for:
The CHEK2 gene (Checkpoint kinase 2) is also a tumor suppressor gene and produces a kinase enzyme protein called CHK2.
Abnormal changes in this gene increase the risk of developing breast cancer by two times. It also increases the risk of:
The PTEN gene produces an enzyme that acts as a tumor suppressor. Almost all tissues in the body have this enzyme in specific quantities. This enzyme prevents the abnormal division of cells by encouraging self-destruction (a process called apoptosis) of these cells. In people with past or present breast cancer diagnoses, variations in this gene can result in an increased risk of:
One of the main non-genetic factors that increase a person’s risk of developing other cancers is radiation exposure.
There are three basic radiotherapy treatment solutions for breast cancer.
1. Three-dimensional Conformal Radiotherapy (3D-CRT)
2. Intensity-Modulated Radiotherapy (IMRT)
3. Volumetric Modulated Arc Therapy (VMAT)
Many studies report a higher risk of second cancer because of radiation exposure.
A large study analyzed the risk of second cancers in 46,176 breast cancer survivors. According to the study, one out of 200 women who had received radiation therapy for breast cancer had a higher risk of being diagnosed with other cancers.
Chemotherapy is a treatment that uses various drugs to kill abnormally growing tumor cells in the body. It is the most common treatment option for cancer.
Some types of chemo drugs given during breast cancer treatment are associated with an increased risk for developing other types of cancers.
Chemo agents that are linked with second cancer risks are:
Patients who go through chemotherapy for a longer time or get treated with higher doses of drugs are at a higher risk of developing other cancers.
While patients who had exposure to radiation therapy and chemotherapy were at higher risk for developing second non-breast cancers, people under the age of 40 who received these treatments were at more risk than the elderly who received treatment.
Smoking increases the risk of breast cancer and all other cancers. Smokers diagnosed with breast cancer are at higher risk for developing other cancers in the future when compared to non-smokers.
A 1994 study tried to find the relationship between smoking, breast cancer, radiation therapy, and the risk of second cancers. According to the study, radiation therapy for breast cancer increased the risk of developing other cancers in smokers and non-smokers. However, in smokers, this risk was much higher.
Genetic testing can be a good aid for treatment planning and risk management if:
Genetic testing will look for specific genes that can increase your risk for breast and other cancers. It will tell you if you are at higher risk for second cancer. In case you belong to the high-risk category, regular screening can help you.
Talk to your doctor about the dosage and type of chemotherapy and radiation treatment you will be receiving for your breast cancer. Some treatments may increase your risk for breast cancer than others.
Some lifestyle changes can lower your risk of developing cancer.
The fear of breast cancer recurrence and the fear of developing second cancers can lead to high stress. Stress causes abnormal changes in the cells and can be a cause for cancer recurrence. Fear and stress lead to unwanted behaviors like alcohol abuse, smoking, and excessive eating. All these also increase the risk of developing other cancers. Practicing mindfulness and talking to a mental health expert might help you in controlling stress.
Smoking remains one of the biggest causes of preventable deaths globally. According to the Centers for Disease Control and Prevention (CDC), smoking accounts for 1 in about five deaths in the United States every year.
As of 2019, 14% of the adult population in the country are smokers.
The American Lung Association states that there are more than 600 ingredients present in a cigarette. Each cigarette releases about 7000 chemicals when it is burnt. Out of these, close to 70 chemicals are proven carcinogens (cancer-causing substances). Some of them are:
When a person inhales cigarette smoke, these carcinogens and other chemicals reach the lungs and are distributed throughout the body.
These CYP enzymes convert these carcinogens into a more active intermediary form called DNA adducts. DNA adducts are parts of the DNA that attach themself to these cancer-causing chemicals.
The intermediaries lead to DNA damage and abnormal cell multiplication and have to be quickly detoxified by other enzymatic processes. Unfortunately, in some people, the number of cancerous intermediaries builds up at a faster rate than they are eliminated. This leads to cancer.
There are other carcinogens in cigarette smoke that directly form DNA adducts without the help of the CYP enzymes. These lead to direct DNA damage and cell abnormalities, and resultant cancer.
While smoking is a risk factor for all types of cancer, it is significantly associated with breast cancer in women.
In the United States, 1 in every eight women will be diagnosed with breast cancer in her lifetime. Smoking increases this risk drastically.
A study published in the BioMed Central Ltd forum analyzed the risk of breast cancer in women who smoked.
102,927 women were chosen and monitored for 7.7 years. In the end, 1815 women developed invasive breast cancer. The study found that smokers had a 14% higher risk of developing breast cancer than non-smokers.
This study also mentions that women who start smoking before 17 had a significantly higher risk (24%) for breast cancer.
Another study analyzed the risk of breast cancer in 111,140 active smokers and 36,017 passive smokers (people who don’t smoke themselves but are exposed to other people’s cigarette smoke).
According to the study, some factors that increase the risk of breast cancer are:
Secondhand smoke is also called passive smoking and is smoke that a person inhales unintentionally. For example, people can inhale tobacco smoke by just being around others who smoke. According to the California Air Resources Board, secondhand smoke is a proven carcinogen.
The smoke that is released from the burning ends of cigarettes is called sidestream smoke. Sidestream smoke is unfiltered and hence contains more harmful substances than the smoke that a smoker breathes out.
A 2013 study analyzed the risk of breast cancer in 322,988 active, passive, and non-smokers.
Compared to non-smoking women, those exposed to passive smoke at home or work had a higher risk of developing breast cancer.
The GSTM1 gene (glutathione S-transferase mu 1 gene) helps produce the glutathione S-transferase enzyme that belongs to the Mu class. The Mu class of enzymes helps in eliminating carcinogens and other environmental toxins from the body.
rs366631 is a single nucleotide polymorphism or SNP in the GSTM1 gene.
People with the GSTM1 null genotype have a higher risk of developing breast cancer when exposed to cigarette smoke.
Null genotype is the non-functional variant of the gene that results in total loss of function of the gene.
Here, the TT genotype is the null genotype.
The risk of breast cancer was also more severe in postmenopausal smokers with the GSTM1 null genotype.
|TT||Increased risk of breast cancer upon smoking|
|CT||Normal risk of breast cancer upon smoking|
|CC||Normal risk of breast cancer upon smoking|
The SLC4A7 gene (Solute Carrier Family 4 Member 7 gene) helps produce a protein that transports sodium and bicarbonate ions. It also plays a role in the metabolism of different acids, ions, and amine compounds.
rs4973768 is an SNP in the SLC4A7 gene. A meta-analysis has reported an increased risk for breast cancer upon smoking in T allele carriers.
|TT||Increased risk of breast cancer upon smoking|
|CT||Increased risk of breast cancer upon smoking|
|CC||Normal risk of breast cancer upon smoking|
There are so many government and private bodies that help people with tobacco addiction. You can get help from some of these rehab centers to stop or limit smoking. It takes time and effort to curb the craving. Here are some pointers that can help you with this.
For people who have been smoking for years together, some places, smells, habits, or environments can create an urge to smoke. Understand these triggers and stay away from them. Practice the below activities to make quitting smoking easier.
Secondhand smoking ends up harmful to non-smokers. Here are ways you can limit/eliminate secondhand smoke exposure.
Genetic testing helps identify genetic factors that could increase your breast cancer risk. If you do have a high genetic risk, regular screening may help.
All of us know that eating a combo of cheesy supersize pizza, bulging burger, and an ice cream sundae is bad for our health. Yet, the craving for the yummy big Mac burger and a tasty cream cake from a roadside shop doesn’t seem to lessen.
Are you someone who has repeatedly tried to control your sweet tooth but remain succumbed to the lures of junk food?
Maybe it is not your fault at all!
Scientists from the National Institute of Allergy and Infectious Diseases in Maryland say so.
According to their findings eating junk food on a regular basis can lead to already known risks of cancer, inflammation, infections, allergic reactions, and permanent scarring in your DNA.
Yes, it is true.
Junk food can alter your DNA and carry on the scar for generations to come altering the mini-ecosystem that exists in our body forever.
It is the foremost cause of obesity and leads to various problems in the immune system and disturbs the intricate chemical makeup of the stomach.
But permanent damage to DNA comes as a shocker as well as a waking call for all the junk food lovers out there!
Our body has evolved over time to adjust to its surroundings and the same goes for the bacteria in the gut.
When you munch on too much junk food, the bacteria in your stomach get affected.
Research has shown that they have already undergone a lot of changes in their gene expressions due to our unhealthy food habits.
Even our DNA has been encoded with our poor dietary choices.
These changes are directly passed on to our off springs stretching across generations.
A mother’s eating habits have a great potential in shaping her child’s flavor and preferences even before birth and determines the child’s choice of food, sugar or vegetable.
The new study also reveals the effect of paternal DNA in molding a child’s food habit.
The developmental imbalances created during a child’s critical developmental period could leave the baby’s immune system weak and may cause autoimmune and allergic diseases.
The only way to counteract this alarming condition is a radical change of lifestyle.
The transfer of strained DNA can be stopped only if the present generation moves towards a healthier diet.
Food without salt is tasteless and unappetizing. But, too much salt intake is not good for health. Of course, our body needs salt but not as much as we consume. Only one gram of salt is essential for an adult in a day and even lesser is the need for salt in children. But people take a lot more salt than is medically recommended which is a concern.
1. High Blood Pressure
The pressure that the blood puts on the blood vessels is known as blood pressure. Many reasons like too much body weight, no exercise as well as too much salt intake could lead to the increase in blood pressure. This could lead to various health complications like a stroke or a heart attack. People think that as they grow older, it is natural for the blood pressure to grow. It is not so. If you control the daily amount of salt in your food, you can keep your blood pressure under check..
2. Stomach Cancer
If a person is high on salt consumption, he/she is more susceptible to getting stomach cancer. A bacteria known as H. Pyroli is the cause for stomach cancer. Now too much salt intake can damage stomach lining, which in turn would leave the stomach vulnerable to H. Pyroli, and increase the chances of developing stomach cancer.
A condition where the bones lose its density and become thin or brittle is known as osteoporosis. Many people around the world suffer from this disorder. Calcium is stored in our bones. Too much salt intake causes this calcium to be flushed out of the body through urine causing the bones to turn weak and brittle. This disorder is very common in women after menopause but this can be checked by consuming lesser amount of salt in the daily diet.
4. Diseases of the Kidney
The kidneys maintain the balance of fluids in the human body. They monitor the amount of fluid which is flushed out from the blood into the urine. Too much salt intake can cause malfunctioning of the kidneys. Also when calcium from the bones is flushed out by the urine, it could cause a deposit to form in the kidneys leading to kidney stone.
5. Retention of Water
Too much salt in the diet could lead to water being retained in the body which could lead to bloating. This can be cured by reducing salt consumption
Hence to reduce health hazards and to lead a normal life it is advisable that people eat more fresh food rather than tinned and junk food as they all have huge quantities of salt in them and thereby increasing your overall salt consumption levels.
Our traits are basically divided into genetic and environmental. Genetic factors are the ones a person is born with, and a large chunk of these factors are inherited from the previous generations. Environmental factors include chemical, physical, nutritional, infectious and behavioural factors. Many prevailing diseases such as diabetes and cancer are caused by the complex interplay of genetic and environmental factors. Both the factors will play a part in influencing the diseases. Some may be more influenced by the genetic factors while others will be largely affected by the environmental factors. But, most of the diseases are always associated with the genetic makeup and many inherited diseases can be influenced by environmental conditions.
If you have a genetic predisposition to antisocial behaviour, you may not demonstrate the trait until you experience abuse or neglect in your childhood. If you have had a stress-free and normal childhood, you will never express this specific genetic trait. The expression of a specific trait towards which you are genetically predisposed can be prevented by protective environmental factors. If you have a predisposition to alcohol abuse and live in an alcohol-prohibited environment, it may not express itself. Thus, protective genetic factors have a comparatively less significant effect if environmental exposure is strong.
Response to environmental exposure depends on the genotype, which is a term that defines your genetic make-up for a specific trait/disease. If you have had stress in your early life, it may cause depression in later years. This is only when certain genotypes are present. A person’s genotype can also determine their response to specific medications and their side-effects through various biochemical mechanisms. There is an entire branch of science that studies this called Pharmacogenomics.
If we can identify our genes and characterize their interactions with the environment, we can have intervention strategies to target them. Therefore, when studying the genetic make-up of individuals to determine their natural predisposition towards certain traits and diseases, it is very important to take into consideration the environmental factors like diet, lifestyle, work environment etc, to be able to characterize their inclination towards these traits and their risk for developing specific diseases.