Learn more on Genomics

All cancers are caused by changes to materials in our bodies called “genes.” These are units of information in every cell of our bodies. Genes tell our bodies which proteins to make based on the type of cell and its needs. Some genes tell our bodies how to fix damage accumulated over time from normal aging, environmental toxins, sun exposure, dietary factors, hormones, and other influences. These damage-controlling genes can repair cells or tell cells when to stop growing and die if there is too much damage to repair.

Cancer is a disease that occurs when cells in our body are damaged and cannot be repaired. These cells can begin to grow and divide abnormally and escape our body’s normal control processes. These abnormal cells are cancer cells.

Cancer cells can grow together as masses called tumors which replace normal cells in tissue or organs. Cancer cells can interfere with the normal functioning of the organ where they arose, and they can also spread to surrounding tissue or through the blood and lymph tissue to other organs. When cancer cells spread beyond their original site to other organs it is called “metastasis.”

Cancer usually develops slowly, often involving multiple steps (damage to multiple genes), over a period of several years. Cancer can usually be treated. Depending on what step or stage the cancer is found, it often can be cured.

Source: www.facingourrisk.org

All cancers are caused by changes to materials in our bodies called “genes.” When genes are damaged, they can develop changes called “mutations.” Over time, damage can accummulate in cells, causing them to grow out of control and cause cancer.

Source: www.facingourrisk.org

It takes more than one gene mutation for cancer to occur. For most people who develop cancer, the cancer-causing gene mutations happen over the course of a lifetime, leading to cancer later in life. Some people are born with a gene mutation that they inherited from their mother or father. This damaged gene puts them at higher risk for cancer than most people. When cancer occurs because of an inherited gene mutation, it is referred to as “hereditary cancer.”

Source: www.facingourrisk.org

Certain diseases, like cancer, can run in families. Cancer can have many causes, but when there are alot of cases of cancers in a family, it could be a sign of “hereditary cancer.”

Hereditary cancers are caused by a gene change, or “mutation” that is present from birth. In most cases, the person with the mutation inherited it from their mother or their father. People with an “inherited gene mutation” have a 50% chance of passing the mutation to each of their children.

There are several different gene mutations that have been associated with increased risk for cancer. Each mutation is different and may be linked with certain risks for specific cancers.

There are blood and saliva tests that can look for inherited gene mutations. There are several different laboratories that offer genetic testing for cancer risk. You can see a list of the labs and tests here. Each lab’s test may differ in several ways:

• which genes they test for
• cost of testing
• name of their test
• how they work with insurance companies
• how they report test results

There are specially trained genetics expert that can provide you with up-to-date information about genetic testing. Cancer is a common disease, so most families will have some members who have had cancer but that does not mean the cancer in that family is hereditary. Contacting a genetics expert is the best way to learn if the cancer in your family is hereditary and to start the genetic testing process.

Source: www.facingourrisk.org

Cancer is a common disease, so most families will have some members who have had cancer. Cancer that is not due to an inherited gene mutation (change) is called sporadic cancer. It is believed that most—perhaps 80%—of all cancers are sporadic. This means even if cancer does not run in a family, a family member can still be at risk for some type of cancer in his or her lifetime.

Sporadic cancer and hereditary cancer differ in several ways that may affect health care decisions:

• Hereditary cancers are caused in part by gene mutations passed on from parents to their children. Other blood relatives may share these same gene changes. Sporadic cancers are believed to arise from gene damage acquired from environmental exposures, dietary factors, hormones, normal aging, and other influences. Most acquired gene changes are not shared among relatives or passed on to children.
• Hereditary cancers often occur earlier than the sporadic form of the same cancer, so experts often recommend different screening, at a younger age for people with a gene mutation or hereditary cancer in their family.
• Hereditary cancers can sometimes be more aggressive than the sporadic form of the same cancer. For example, hereditary prostate cancers tend to be more aggressive and more likely to spread than sporadic prostate cancers.
• Hereditary cancers may respond to different treatments than sporadic cancers. For example, PARP inhibitors are drugs that were designed to treat cancers associated with BRCA mutations. The agent Keytruda has been approved for treating cancers in people with one of the mutations that causes Lynch Syndrome.
• Individuals who have inherited a gene change may be at a higher risk for more than one type of cancer. For cancer survivors, this may affect cancer treatment options, prevention, or follow-up care.

Source: www.facingourrisk.org

There may be signs that point to an inherited mutation within a family. Sometimes the signs are as simple as a single family member being diagnosed with a certain type of cancer. Other signs require looking more closely at many family members across several generations to pick up certain patterns of cancer. Different gene mutations can cause different types of cancer. Read more about the signs of hereditary breast, ovarian, and related cancers (also known as HBOC).

Source: www.facingourrisk.org

Changes in BRCA1 and BRCA2 are most closely associated with increased risk for breast cancer and ovarian cancer.

Other cancer syndromes can increase the risk for breast or ovarian cancer and may have other signs as well:

• Lynch syndrome, aslo known as Hereditary Non-Polyposis Colorectal Cancer (HNPCC) is a hereditary syndrome that can increase the risk for the following cancers:
  • colon (particularly under age 50)
  • ovarian
  • endometrial (uterine)
  • stomach
  • small intestine
  • bile duct
• Cowden Syndrome (PTEN mutation) can increase the risk for the following cancers:
  • breast
  • thyroid (non-medullary)
  • Cowden Syndrome can also cause distinct skin lesions
• Peutz-Jegher Syndrome (STK11 mutation) can increase the risk for the following cancers:
  • colon
  • breast
  • pancreas
  • Peutz-Jegher Syndrome can also cause multiple pigmented spots on lips and inner cheeks
• Li-Fraumeni Syndrome (TP 53 mutation) can increase the risk for the following cancers:
  • breast
  • sarcomas (bony and soft-tissue)
  • brain tumors
  • childhood adrenocortical carcinomas

Other hereditary mutations have been identified that don’t increase the risk for breast or ovarian cancers but do increase the risk for other cancers. Any family with multiple individuals with the same cancer, very young onset cancers, or rare cancer types should consult with a genetics specialist regarding whether the cancer in family might be hereditary.

Additionally, there are families with multiple cases of breast cancer and/or ovarian cancer in which no mutation has been identified. These familial cancers likely have a hereditary component but the genetic cause has not yet been identified.

Source: www.facingourrisk.org

Cancer is a common disease, so most families will have some members who have had cancer. Cancer that is not due to an inherited gene mutation (change) is called sporadic cancer. It is believed that most—perhaps 80%—of all cancers are sporadic. This means even if cancer does not run in a family, a family member can still be at risk for some type of cancer in his or her lifetime.

Sporadic cancer and hereditary cancer differ in several ways that may affect health care decisions:

• Hereditary cancers are caused in part by gene mutations passed on from parents to their children. Other blood relatives may share these same gene changes. Sporadic cancers are believed to arise from gene damage acquired from environmental exposures, dietary factors, hormones, normal aging, and other influences. Most acquired gene changes are not shared among relatives or passed on to children.
• Hereditary cancers often occur earlier than the sporadic form of the same cancer, so experts often recommend different screening, at a younger age for people with a gene mutation or hereditary cancer in their family.
• Hereditary cancers can sometimes be more aggressive than the sporadic form of the same cancer. For example, hereditary prostate cancers tend to be more aggressive and more likely to spread than sporadic prostate cancers.
• Hereditary cancers may respond to different treatments than sporadic cancers. For example, PARP inhibitors are drugs that were designed to treat cancers associated with BRCA mutations. The agent Keytruda has been approved for treating cancers in people with one of the mutations that causes Lynch Syndrome.
• Individuals who have inherited a gene change may be at a higher risk for more than one type of cancer. For cancer survivors, this may affect cancer treatment options, prevention, or follow-up care.

Source: www.facingourrisk.org

“Hereditary cancers” are those caused by an inherited gene mutation that increases the risk for one or more types of cancer. “Hereditary Breast and Ovarian Cancer Syndrome” (also known as HBOC) is most commonly caused by mutations in one of two genes: BRCA1and BRCA2. These mutations increase the risk for breast, ovarian, pancreatic, prostate, melanoma and possibly other cancers. Mutations in other genes are also associated with hereditary breast and/or ovarian cancers including PALB2, CHEK2, ATM, BRIP1, and RAD51C, and RAD51D. People with the following personal or family history should discuss the possibility of genetic testing with a genetic counselor:

If you or a relative have had any of the following:

• ovarian, fallopian tube, or primary peritoneal cancer
• breast cancer at age 50 or younger
• two separate breast cancers
• a type of breast cancer called “triple negative breast cancer”
• male breast cancer
• pancreatic cancer
• prostate cancer at age 55 or younger or metastatic prostate cancer (cancer that spread outside the prostate)
• Eastern European Jewish ancestry and any of the above cancers at any age

Or, if more than one family member on the same side of your family has had:

• breast cancer
• ovarian, fallopian tube, primary peritoneal cancer
• prostate cancer
• pancreatic cancer

Several other types of cancer syndromes have been identified, each with a particular set of signs. Some of these syndromes increase risk of breast cancer including Cowden syndrome (PTEN mutation), Li Fraumeni syndrome (TP53 mutation), CDH1 mutations, and STK11mutations. Lynch Syndrome is a hereditary cancer syndrome that increases risks of many cancers, including colon, uterine, and ovarian.

If you would like to learn if the cancer in your family is hereditary, it is important to consult with a genetics expert. You can find a cancer genetics specialist on our finding health care section.

Source: www.facingourrisk.org

Pharmacogenomics uses information about a person’s genetic makeup, or genome, to choose the drugs and drug doses that are likely to work best for that particular person. This new field combines the science of how drugs work, called pharmacology, with the science of the human genome, called genomics.

Source: www.genome.gov

Until recently, drugs have been developed with the idea that each drug works pretty much the same in everybody. But genomic research has changed that “one size fits all” approach and opened the door to more personalized approaches to using and developing drugs.

Depending on your genetic makeup, some drugs may work more or less effectively for you than they do in other people. Likewise, some drugs may produce more or fewer side effects in you than in someone else. In the near future, doctors will be able to routinely use information about your genetic makeup to choose those drugs and drug doses that offer the greatest chance of helping you.

Pharmacogenomics may also help to save you time and money. By using information about your genetic makeup, doctors soon may be able to avoid the trial-and-error approach of giving you various drugs that are not likely to work for you until they find the right one. Using pharmacogenomics, the “best-fit” drug to help you can be chosen from the beginning.

Source: www.genome.gov

Doctors are starting to use pharmacogenomic information to prescribe drugs, but such tests are routine for only a few health problems. However, given the field’s rapid growth, pharmacogenomics is soon expected to lead to better ways of using drugs to manage heart disease, cancer, asthma, depression and many other common diseases.

One current use of pharmacogenomics involves people infected with the human immunodeficiency virus (HIV). Before prescribing the antiviral drug abacavir (Ziagen), doctors now routinely test HIV-infected patients for a genetic variant that makes them more likely to have a bad reaction to the drug.

Another example is the breast cancer drug trastuzumab (Herceptin). This therapy works only for women whose tumors have a particular genetic profile that leads to overproduction of a protein called HER2.

The U.S. Food and Drug Administration (FDA) also recommends genetic testing before giving the chemotherapy drug mercaptopurine (Purinethol) to patients with acute lymphoblastic leukemia. Some people have a genetic variant that interferes with their ability to process the drug. This processing problem can cause severe side effects and increase risk of infection, unless the standard dose is adjusted according to the patient’s genetic makeup.

The FDA also advises doctors to test colon cancer patients for certain genetic variants before administering irinotecan (Camptosar), which is part of a combination chemotherapy regimen. The reasoning is that patients with one particular variant may not be able to clear the drug from their bodies as quickly as others, resulting in severe diarrhea and increased infection risk. Such patients may need to receive lower doses of the drug.

Source: www.genome.gov

Much research is underway to understand how genomic information can be used to develop more personalized and cost-effective strategies for using drugs to improve human health.

In 2007, the FDA revised the label on the common blood-thinning drug warfarin (Coumadin) to explain that a person’s genetic makeup might influence response to the drug. Some doctors have since begun using genetic information to adjust warfarin dosage. Still, more research is needed to conclusively determine whether warfarin dosing that includes genetic information is better than the current trial-and-error approach.

The FDA also is considering genetic testing for another blood-thinner, clopidogrel bisulfate (Plavix), used to prevent dangerous blood clots. Researchers have found that Plavix may not work well in people with a certain genetic variant.

Cancer is another very active area of pharmacogenomic research. Studies have found that the chemotherapy drugs, gefitinib (Iressa) and erlotinib (Tarceva), work much better in lung cancer patients whose tumors have a certain genetic change. On the other hand, research has shown that the chemotherapy drugs cetuximab (Erbitux) and panitumumab (Vecitibix) do not work very well in the 40 percent of colon cancer patients whose tumors have a particular genetic change.

Pharmacogenomics may also help to quickly identify the best drugs to treat people with certain mental health disorders. For example, while some patients with depression respond to the first drug they are given, many do not, and doctors have to try another drug. Because each drug takes weeks to take its full effect, patients’ depression may grow worse during the time spent searching for a drug that helps.

Recently, researchers identified genetic variations that influence the response of depressed people to citalopram (Celexa), which belongs to a widely used class of antidepressant drugs called selective serotonin re-uptake inhibitors (SSRIs). Clinical trials are now underway to learn whether genetic tests that predict SSRI response can improve patients’ outcomes.

Source: www.genome.gov

Yes. Besides improving the ways in which existing drugs are used, genome research will lead to the development of better drugs. The goal is to produce new drugs that are highly effective and do not cause serious side effects.

Until recently, drug developers usually used an approach that involved screening for chemicals with broad action against a disease. Researchers are now using genomic information to find or design drugs aimed at subgroups of patients with specific genetic profiles. In addition, researchers are using pharmacogenomic tools to search for drugs that target specific molecular and cellular pathways involved in disease.

Pharmacogenomics may also breathe new life into some drugs that were abandoned during the development process. For example, development of the beta-blocker drug bucindolol (Gencaro) was stopped after two other beta-blocker drugs won FDA approval to treat heart failure. But interest in Gencaro revived after tests showed that the drug worked well in patients with two genetic variants that regulate heart function. If Gencaro is approved by the FDA, it could become the first new heart drug to require a genetic test before prescription.

Source: www.genome.gov

• Pharmacogenomics
  From the NHGRI’s Talking Glossary of Genetic Terms
• Pharmacogenomics Fact Sheet [nigms.nih.gov]
  From the National Institute of General Medical Sciences
• What is pharmacogenomics? [ghr.nlm.nih.gov]
  From Genetics Home Reference
• Pharmacogenomics [learn.genetics.utah.edu]
  From the Genetic Science Learning Center

Source: www.genome.gov

A genetic disorder is a disease caused in whole or in part by a change in the DNA sequence away from the normal sequence. Genetic disorders can be caused by a mutation in one gene (monogenic disorder), by mutations in multiple genes (multifactorial inheritance disorder), by a combination of gene mutations and environmental factors, or by damage to chromosomes (changes in the number or structure of entire chromosomes, the structures that carry genes).

As we unlock the secrets of the human genome (the complete set of human genes), we are learning that nearly all diseases have a genetic component. Some diseases are caused by mutations that are inherited from the parents and are present in an individual at birth, like sickle cell disease. Other diseases are caused by acquired mutations in a gene or group of genes that occur during a person’s life. Such mutations are not inherited from a parent, but occur either randomly or due to some environmental exposure (such as cigarette smoke). These include many cancers, as well as some forms of neurofibromatosis.

Genetic disorders typically involve the inheritance of a particular mutated disease-causing gene, such as sickle cell disease, cystic fibrosis, and Tay-Sachs disease. The mutated gene is passed down through a family, and each generation of children can inherit the gene that causes the disease. Rarely, one of these monogenic diseases can occur spontaneously in a child when his/her parents do not have the disease gene, or there is no history of the disease in the family. This can result from a new mutation occurring in the egg or sperm that gave rise to that child.

Most genetic disorders, however, are “multifactorial inheritance disorders,” meaning they are caused by a combination of inherited mutations in multiple genes, often acting together with environmental factors. Examples of such diseases include many commonly-occurring diseases, such as heart disease and diabetes, which are present in many people in different populations around the world.

Research on the human genome has shown that although many commonly occurring diseases are usually caused by inheritance of mutations in multiple genes at once, such common diseases can also be caused by rare hereditary mutations in a single gene. In these cases, gene mutations that cause or strongly predispose a person to these diseases run in a family, and can significantly increase each family member’s risk of developing the disease. One example is breast cancer, where inheritance of a mutated BRCA1 or BRCA2 geneconfers significant risk of developing the disease.

Source: www.genome.gov