Thursday, January 20, 2022

INHERITING CANCER (feat: Genetic & Genomic Testing)

CANCER HEREDITY
(Originally published 11/2020) Cancer is a genetic disease—that is, cancer is caused by certain changes to genes that control the way our cells function, especially how they grow and divide. Genes carry the instructions to make proteins, which do much of the work in our cells. Certain gene changes can cause cells to evade normal growth controls and become cancer. For example, some cancer-causing gene changes increase production of a protein that makes cells grow. Others result in the production of a misshapen, and therefore nonfunctional, form of a protein that normally repairs cellular damage.  

Inherited genetic mutations play a major role in about 5 to 10 percent of all cancers. Researchers have associated mutations in specific genes with more than 50 hereditary cancer syndromes, which are disorders that may predispose individuals to developing certain cancers. Genetic tests for hereditary cancer syndromes can tell whether a person from a family that shows signs of such a syndrome has one of these mutations. These tests can also show whether family members without obvious disease have inherited the same mutation as a family member who carries a cancer-associated mutation. [1]


Everyone has two copies of each set of genes from both parents. If a person inherits a mutation in a Lynch syndrome gene, they still have the normal copy of the gene from the other parent. Cancer occurs when a second mutation affects the normal working copy of the gene, so that the person no longer has a copy of the gene that works properly. Unlike the inherited Lynch syndrome mutation, the second mutation would not be present throughout the person’s body, but would only be present in the cancer tissue. However, not everyone with Lynch syndrome will get cancer. You and your family members are more likely to have Lynch syndrome if your family has a strong history of colorectal cancer. Family members who inherit Lynch syndrome usually share the same mutation. If one of your family members has a known Lynch syndrome gene mutation, other family members who get genetic testing should be checked for that mutation. (source: CDC.gov)

GENETICS & GENOMICS: SIMILAR BUT DIFFERENT

Excerpted from https://robertaklinemd.com


Genetics and genomics sound alike and are often used interchangeably. While they both deal with changes in our DNA, there are important scientific and clinical distinctions.

GENETICS CAME FIRST
The science of genetics is classically defined as the study of heredity, or how traits are passed on from one generation to the next. While modern day genetics evolved from Gregor Mendel’s pea experiments in the mid-1800s, it wasn’t until James Watson and Francis Crick discovered the actual structure of DNA in 1953 that we began to understand exactly how it works. 

DNA contains the genetic code, the blueprint for everything that happens in our bodies. DNA is short for deoxyribonucleic acid, and it is composed of long strands made up of four different nucleotides called adenine, guanine, thymine, and cytosine, or A, G, T, and C for short. It exists as two long strands that are paired in a specific manner. The DNA is grouped into functional units called genes, which can comprise either a small or large section of DNA.

This DNA code is incredibly complex, and in order to contain all this information, the amount of DNA we each have in our cells is tremendous. In fact, every cell contains about 6 feet of DNA. That’s enough DNA in one person that, if stretched out, it would be long enough to go to the sun and back more than 300 times… or go around the earth’s equator 2.5 million times!

That’s where chromosomes come in. The DNA is compressed into tightly coiled structures called chromosomes in order to fit into our cells. We each have 23 pairs of chromosomes, and they are stored in a special compartment of the cell called the nucleus. 

While that solves the storage problem, it creates a different problem – how to access the instructions encoded in the DNA. Every time that cell needs to replicate itself to replace dead cells in an organ or tissue, or we need to make a certain protein, portions of the chromosome need to be unwound to expose the needed genetic code. But sometimes during that process mistakes are made, and the change in the DNA can be mild or catastrophic.

GENETICS: BLACK & WHITE
Genetics traditionally deals with changes in the DNA sequence called mutations that are inherited in a predictable manner. These can involve small sections of DNA all the way up to whole chromosomes. Medical genetics has traditionally focused on health conditions that are due to inherited mutations in single genes (Huntington disease), in whole chromosomes (trisomy 21 or Down syndrome) or are associated with birth defects or developmental disabilities. 

With a traditional, single-gene disorder such as Tay-Sachs disease, genetic information is obtained from a patient as well as his or her immediate family members and relatives. The information is then used to diagnosis or predict the risk of an inherited genetic disorder passing from one generation to another. For many single-gene disorders, there are very limited medical interventions available. Genetic disorders are individually rare, and they account for about 5% of all human disease.

That meant 95% of the diseases were due to some other mechanism. In an effort to better understand how DNA contributes to health, scientists realized that genetic mutations were only part of the story. The Human Genome Project was conceived in the late 1980’s to provide answers.

One of the biggest take-aways from the Human Genome Project was that humans share 99.5% of their genome. But while this means we are far more alike with all the genes we have in common, that 0.5% difference is significant. The small differences are what make us each unique.


Genomic Medicine: It is now possible to use results from clinically-based genomic testing to evaluate a person’s disease susceptibility, and develop evidence-based, personalized intervention strategies to reduce those risks. These strategies include DNA-directed lifestyle modifications, dietary recommendations, nutritional supplements and/or exercise, all of which influence how these genes function to create health or disease. Biomarker testing can then be used to evaluate whether the intervention is efficacious. With this approach, the guess-work and inefficiencies of trial-and-error strategies are greatly reduced, leading to better health more quickly and cost-effectively.

A comprehensive test can provide gender-specific reports to create personalized programs for many health conditions, including:

  • Prevent ER+ breast cancer or its recurrence in women diagnosed with the condition
  • Reverse osteopenia and osteoporosis
  • Prevent or treat Type II diabetes, heart disease, stroke, metabolic syndrome and obesity.
  • Optimize athletic performance
  • Customize nutrient requirements and resolve nutritional paradoxes
  • Prevent, treat and manage depression and anxiety
  • Plus many more health and wellness issues
  • Genomic Medicine is personalizing healthcare with precision. 

To see complete article, visit: https://robertaklinemd.com/


About the Author

BOBBI KLINE, MD 
(Educational Dir. /Women's Diagnostic Group)
Dr. Kline is a board-certified ObGyn physician, Integrative Personalized Medicine expert, consultant, author, and educator whose mission is to change how we approach health and deliver healthcare. She helped to create the Integrative & Functional Medicine program for a family practice residency, has consulted with Sodexo to implement the first personalized nutrition menu for healthcare facilities, and serves as Education Director for several organizations including the Women’s Diagnostic Health Network, Mommies on a Mission. Learn more at https://bobbiklinemd.com 





Directory of Inherited Cancer Syndromes source: NIH LINK
• BRCA1 / BRCA2 - breast & ovarian cancer
• Cowden Syndrome
• Diaphyseal medullary stenosis
• Duodenal carcinoid syndrome
• Endolymphatic sac tumor
• Familial adenomatous polyposis
• Familial isolated pituitary adenoma
• Gardner syndrome
• Hereditary diffuse gastric cancer
• Hirschsprung disease ganglioneuroblastoma
• Langerhans cell histiocytosis
• Li-Fraumeni syndrome
• Lynch syndrome
• Multiple endocrine neoplasia:
- (type 1
 | type 2A | type 2B)
• MYH-associated polyposis
• Oslam syndrome
• Paraneoplastic Neurologic Disorders
• Perlman syndrome
• Pheochromocytoma | islet cell tumor synd.
• Premature aging Okamoto type
• Stewart Treves syndrome
• Von Hippel-Lindau disease
• WAGR syndrome

 LYNCH SYNDROME is a hereditary cancer condition in which a mismatched repair gene, which ordinarily repairs errors in DNA duplication, is defective. As a result, individuals are predisposed at a very high lifetime risk of cancer, including an up to 85% risk for colorectal cancer, 65% risk for uterine cancer, 19% risk for gastric cancer, 13% risk for ovarian cancer and a higher than average risk for other cancer including cancers of the liver, gallbladder, kidney, bladder, prostate, pancreas, skin, brain and breasts. With genetic testing, there is hope...once diagnosed, annual cancer screenings take place and cancers can be treated or removed before becoming life threatening. By knowing our family history and having a great medical team, we live longer than ever before...as long as anyone else!




An Introduction to Lynch Syndrome
By: Lindy Bruzzone

I was diagnosed in 2007 with colorectal cancer which was tied to my having Lynch Syndrome.  There are tens of thousands of people now diagnosed with this genetic disorder which means this is NOT a RARE disorder like most might think.  It came from a defective mismatch repair gene, where instead of repairing errors in DNA replication, it puts in different proteins and create more errors than it tries to keep doing. 

I produced this video 10 years after I lost lost my father. It was just so difficult for me to lose him that way. The day before he died, he said to me, "the doctors think it's hereditary, go get checked and tell your brother and sister, to get checked."  After his funeral, my brother and I started looking for the right cancer center to get help. Knowing my father's reports, my surgeon and other doctors jumped in to get me tested, and sure enough--- it was positive. 

That's why Lynch Syndrome International was developed because nobody was getting diagnosed. NOW they are! And then when Color Genomics was developed (a Steve Jobs startup offering for FREE genetic testing), suddenly everybody started getting tested because they could finally afford it. They didn't want insurance companies involved. It took care of every barrier that we have to testing for hereditary cancers. 

tbc


References

1) Cancer Heredity / NIH: https://www.cancer.gov/about-cancer/causes-prevention/genetics