Understanding Lynch Syndrome and Cancer Risk

This video explains Lynch syndrome, a hereditary cancer predisposition caused by germline mutations in mismatch repair (MMR) genes. It details how these gene defects impair DNA replication error correction, leading to increased cancer risk. The presentation by Dr. Deanna Windham also touches upon LDN and Lynch syndrome's implications across various cancer types.
 

Dr. Deanna Windham, DO: Lynch syndrome is actually caused by a germline mutation. That means one that happens in uterero before birth. Uh the mutation is in one of four mismatch repair genes. Mismatch repair genes. If you go all the way back to your high school chemistry class and you remember the DNA double helix and the way that our DNA replicates is by basically unzipping the RNA copies that code and then the DNA zips back up. Well, during that process of the copying or replication, there are often times incorrect pairing of the nucleotide bases. So those nucleotide bases are a T and CG and those need to be matched together. But sometimes an A will be matched with a G or a T to a C. And in those cases, our M mismatch repair genes repair that mismatch. But in people that have Lynch syndromes, they've inherited a mutation in one of these M mismatch repair genes. And so they are born with one functional LL or one functional copy and one nonfunctional copy of those of that gene. Inheriting just that one co one dysfunctional copy though does not increase the risk of cancer. It is when there is an epigenetic mutation which is a mutation acquired during your lifetime that changes the functional AL and then there are two dysfunctional ALS in the mismatch repair genes paired together and that's when the increased risk of cancer occurs.