telomeres

Ever notice when you get something in your head you start seeing that thing everywhere? I remember when I was a teenager I wanted a cordless telephone. I begged my parents for one with the claim that "everyone had one."  It did seem like they did: Carrie, my short, rebellous friend would walk around her house on one for hours, Monica down the street had one she'd hide from her brother, Radio Shack had them prominently on display. It felt like I was the only person without one and I had the 1980s version of FOMO.

 

This year has been the year of the telomere for me.  Everywhere I look there is talk about telomeres.  Telomeres are much nerdier than cordless phones were in the 1980s, but once you are in your 40s, cool is less important than health and telomeres predict health and fertility.

 

Telomeres are the caps on the ends of our chromosomes.  They keep the chromosomes from breaking off at the ends so we don't lose DNA (chromosomes are made up of strands of DNA).  How have telomeres been all the buzz for me this year?

1. I was reading a book about amazing women in history to my daughters and Barbara McClintock, an American cytogeneticist, won a Nobel Prize for identifying telomeres back in the 1930s.

2. I've been following the NASA Twin Study which looked at (among a million other things) telomere length in the identical twin who was in space, compared to the twin who stayed on earth.

3. I am worried about my telomeres as they correlate closely with the chance of developing cancer, heart disease and they relate to overall length of life.

4. Telomeres play a role in fertility.

 

Telomeres are important protectors of the integrity of the DNA in the chromosomes.  If they start to shorten we see more cell degeneration.  Telomeres are naturally shortening with age as the more cells replicate and turn over the more likely there are breaks in the telomere.  So long telomeres = good and short telomeres = bad.  What keeps telomeres long is an enzyme call telomerase.  Not all cells have telomerase. Most of our cells don't and so telomeres just get progressively shorter with age.  Stem cells and the endometrium do have telomerase which is likely why the endometrium can work your whole life, as long as there is estrogen around to make it grow.  This means the endometrium doesn't age.  Very cool.  This is why we can get women pregnant at any age (not with her eggs as they age, but with her uterus).  

 

There is research being done now looking at telomerase levels and telomere length in women's endometriums to see if it correlates with embryo implantation and fertility.  There maybe a group of women with abnormal endometrial cell telomere length or telomerase levels whose endometriums can't support a pregnancy. This would be useful information as we could treat them (one day!) or direct them to surrogacy.  We will definitely be early adopter of any clinical application that extends from this work.  It's out patient-directed FOMO. 

 

It's interesting stuff.   To read more: https://www.ncbi.nlm.nih.gov/pubmed/27979878

Dr. Beth Taylor MD, FRCSC
Reproductive Endocrinology & Infertility