Group 2 - TRPM8*

TRP

ion potentials that sense heat or cold - 2 types - group 1 - and group 2

trpm8

cold sensitive ion channel gets activated from 25-18 degrees and cooling agrents.

how it works

activated on plasma membrane, ions lke sodium and calcium enter cells, leads to depolarization and generation of action potential and is in sensory nuerons and bladder.

factors

mutations can affect how intensively how one feels cold, as well as age and sex and geography

genetic basic of trpm8

located on chromosome 2 and contains 1104 amino acids, some activate to mild to extreme cold and carry throughout nervous system to the brain

population variability

lots of polymorphism. - rs10166942, varient

rs10166942 frequency

C allele, in higher in warmer regions in africa (95% in Yoruba population). T allele high in colder regions 88% europe

evolutionary forces

TRPM8 focuses on cold perception its had selection advantage, increase altitude and temp decreases, 88% frewuency in europe. as weve movede to colder eras, better for senstivity

mating practices

survival driven mate selection -> more sensitivity to cold will survive better, reproductive success in harsh climates. gene flow and migration (movement and intermarrige)