Diversity of Human Clock Genotypes and Consequences - Progress in Molecular Biology and Translational Science - page 74

we learn more regarding the molecular underpinnings of the biological pro-
cesses involved and as our phenotyping techniques improve, using animal
models to investigate themechanistic alterations caused by these human clock
gene variants will become more effective and fruitful.
In the past few decades, much effort has been devoted into understanding
what constitutes the circadian clock and how the clock functions. Thus, we
currently have a handful of “clock genes” and a relatively clear picture of the
molecular mechanisms regarding how these genes act together to set the
phase and amplitude of the clock. One of the next big challenges in the field
is answering the “ why ” question, that is, why is the clock built this way, or an
even more fundamental question, why do we need a clock. At the individual
level, investigating the broad consequences of alterations in clock genes will
help us understand the function of the clock and the role it plays in our over-
all well-being. At a population level, studying the distribution of clock geno-
types and associated phenotypes across the world will facilitate unveiling the
interactions between the molecular clock and environment. Insights gained
from these studies shall provide answers to some of the most fundamental
questions in human circadian biology. Only with such understanding can
we maximize the health benefits and therapeutic values of the circadian
clock.

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