Monday, November 9, 2020

Genetics and our Variation in Height

In the article, Growth Spurt for Height Genetics by Jocelyn Kaiser, she describes the impact genetics plays in people's height. Studies of fraternal and identical twins show that 80% of their variation in height is genetic. However, data from more 4 million people from 200 studies by the genomewide association (GWA) shows that genetics has less of an impact in the general population than the twin populations studied. These studies show that genetics alone is only responsible for 40-50% of the variability in the population. They also show that common variants make up most of these differences. This didn't explain why genetics were more important in twins' height though. Peter Visscher suggested that the extra 30% came from rare variants that twins would be more likely to share than two people in the general population would. I thought this was interesting because we only know the DNA makers responsible for our differences in height, not the actual genes yet. Also, I always assumed height was almost all genetic, I didn't know that environmental factors had such a big impact on our height. 


  1. I also assumed height was all genetics. I never thought of twins having height that is different. This is very interesting. When thinking about it, I would assume all paternal twins would be the same height. I wonder be curious to know if they tested this one both kinds of twins or even triplets, how the height would vary.

  2. I never realized how little environmental factors actually effect our height. Growing up you always heard smoking, drinking coffee and other random things would stunt your growth and that excessive stretching and working out would actually help you grow taller. Now I know this is all lies and that genetics constitutes most of why we are the height that we are.