Development & genetic determinants of height

Genetic Determinants of Height Growth Assessed Longitudinally from Infancy to Adulthood in the Northern Finland Birth Cohort 1966. Here's the important part from the discussion:

To summarise, our results show that nearly half of the genetic variants associated with adult height in this sample had a measurable effect on PHV [peak height velocity] in infancy or puberty. Only one variant was associated with PHV in both infancy and puberty. We found suggestive evidence that the associations of some of the variants may be age-dependent. The majority of signals associated with growth parameters in this study lie close to genes that are involved in recognised growth and development pathways, or have a potential role in growth through an effect on gene expression or regulation (e.g. cell proliferation, bone formation and growth hormone signalling pathways). Heritability of adult height is well documented...but heritability of height velocity at different stages of growth is less well established, although some estimates have been provided from family and twin studies...Our study is the first population based genetic study of longitudinal height growth, and provides an insight into how height in humans may be regulated by its genetic determinants during different periods of growth.

1) As noted in this study around 80-90% of the population wide variation in adult height is heritable in developed societies. This means that 80-90% of the variation within the population is due to variation in genes within the population. In other words, the distribution of heights within one's family can be used to generate a potential distribution of heights for a given individual. For example,

Expected Offspring Height = (Average Parental Value In Standard Deviation Units) +/- Standard Deviation Units

The same logic behind the little javascript I wrote last year.

2) But the effect sizes of the genes which control height are very small. Dan MacArthur recently blogged a paper which showed that 19th biometrical methods are far better at predicting height than modern genomics. We got a long way to go.