Hello there bloggies!
We all come in different sizes and shapes. If you take a random sample of people, you’ll find short people, tall people, and average height people. You’ll be well aware of this if you’ve ever had to ask for someone to reach the top shelf for you. Or if you’ve ever head your head on the top of a plane door or tree branch (trust me, it hurts!).
Now Dr. F, this is a science-related blog <sometimes>. Why the hell are you talking about how tall people are?
Well, a paper was recently published in Nature examining the genetics of height caught my eye. Here is a link to the pubmed entry. Unfortunately, the pdf is behind a stupid pay wall…grrrrr.
Anyway in this massive paper, the investigators examined the genetic contributors of human height in over 700,000 individuals. That’s more than the populations of cities like Denver, Atlanta, and Boston! Specifically, they focused on the associations of rarer and lower frequency genetic variants with height. These associations are usually missed by GWAS (check out a quick entry of GWAS here). The authors added over 80 associated genetic loci to the over 700 previously identified loci.
All of that sounds impressive. But who cares? Why spend the time, effort, and money on teasing apart the genetics of human height?
Well, here are a few reasons:
Height is actually relevant to human health and biology
There are human conditions where height, growth, and development are main features. Dwarfism, pituitary disorders, and other congenital disorders can all have height related presentations. Figuring out which genes influence height can inform the possible problems in disease. Not only that, these disorders can reveal the pathways that govern human height and help us understand the underlying biology.
Easy to measure in large numbers
Some traits like brain MRI imaging, blood metabolites, and gene expression are really hard to measure. Guess what isn’t? Height. All you need is a tape measure! So you can measure it in a fairly standardized manner in a lot of people. Well in over 700,000 individuals like they did in this paper! Such large sample sizes are needed in genetic association studies. They allow for the more statistically powered detection of associations.
Highly heritable polygenic trait
Human height is often described as a classically heritable, polygenic trait. That means many different genes play a huge role in determining how tall a person is. So performing performing human genetics studies on height makes perfect sense. You need genetic studies in order to dissect the biological pathways that influence height.
Test out methods and build collaborations
Since height is highly heritable, polygenic, and can be measured in loads of people, it is the perfect test trait to try out new analytical methods and build new collaborations. These new analytical methods and frameworks including the many consortia that exist can then be used to interrogate other traits that may have more direct links to public health (e.g., type 2 diabetes, cardiovascular disease, and Alzheimer’s Disease).
So even though human height doesn’t intuitively have a direct effect on public health, the genetic studies of height have added so much to the field of human genetics. They have been on the forefront of the field and will continue to lead the investigation of other traits.
Hope you enjoyed this brief foray into the genetics of human height. What do you think about studying the genetics of height? Any other traits that stand out? Let me know in the comments below or on twitter @DrFsThoughts.
Thanks for stopping by!