One Singular Deletion…

Everyone that knows me knows I love love love genetics. I have not talked about genetics yet because I didn’t want to lose people in the jargon (or out of boredom). To change that, I decided to spark your interest in genetics with a super rare genetic condition I did a project on in college: Progeria.

Progeria (aka: Hutchinson–Gilford syndrome) is a genetic disease that causes early aging. It occurs in about 1 in 4 million births. Children born with this condition look average when they pop out, but within a few months they show a lack of growth. Kids with progeria will develop normally mentally, but physically they will be much smaller, with aged looking skin, extreme hair loss and undersized jaw and face bones compared to their larger skulls. With progeria, a 7 year old will face ailments that most people will not begin experiencing until their 50s, including hip problems, arthritis, and heart issues. Unfortunately there is no treatment or cure for progeria and the condition is fatal. Most progeria patients die by the age of 13 due to heart attack or stroke.

I know! I know! Wow, Robert, way to post a sad one. I did it because I want to show you how crazy genetics can be…

You would think a person born with progeria must have a bunch of genes and DNA screwed up or missing. Here is the crazy part – only 1 thing is different. That’s it - one single difference between a normal baby and a baby born with progeria.

Everyone flash back to middle school biology and learning about DNA. DNA is made up of A, T, C and G and the order of those letters determine what the gene does. Well in the middle of your first chromosome there is a gene called the lamin A gene. This gene encodes for the Lamin A protein. 1,824 letters into this gene, a single letter is screwed up and replaced with another (wrong) letter. This is known as a point mutation. You do not inherit point mutations, nor do pass them along – they just happen. They can cause good or bad results and occur all of the time. Your body has lots of ways of trying to fix them, but that’s a whole different post. This mutation in the lamin A gene causes a snowball effect in the body and ends up making the Lamin A protein non-functional. This Lamin A protein is known to help stabilize the nucleus of cells in the body – a SUPER important job. With it not working, the nucleus is unstable and then you get more of a snowball effects until you end up with progeria.

Isn’t that crazy? There are over 3 billion pairs of letters in the human genome and a mistake in only one can have such catastrophic events.

That’s why I think genetics is amazing.