PREVALENCE OF GENETIC VERSUS ENVIRONMENTAL-FACTORS IN HUMAN FEMALE TEMPORAL ORGANIZATION - PRELIMINARY-ANALYSIS

Genetic diversity among ethnic groups is studied by comparing the gene tic fingerprint of the examined groups. This index is constructed by a ggregating the differential frequencies of various marker characterist ics. Recent advances in the study of human biological rhythms may prov ide new indexes that will complement the genetic profile of a populati on, One of the rhythm parameters that is especially useful for this pu rpose is the acrophase (peak time location). The aim of the present st udy is to construct a rhythm profile based on acrophase distribution f or various human groups and to estimate the contribution of genetic an d environmental factors to that profile. The rhythm profiles were cons tructed by comparing the acrophases of 11 plasma hormones in women fro m three different ethnic-geographic populations (North Americans, Roma nians, and Japanese) with reference to three age groups (adolescence-e arly postpuberty, young adulthood, and postmenopause), Genetic distanc es of these ethnic groups were determined by 14 genetic markers. Clust er and principal coordinates analyses were used to define the variatio n of the two parameters (genetic distances and acrophase dispersion), The analyses show that North Americans and Romanians are closer to eac h other with regard to both parameters and far apart from the Japanese . However, there was a difference between the variation presented by t he first eigenvalue of the genetic profiles (94.5%) and that of the fi rst eigenvalue of the acrophase pattern (69.1%), which means reduction in the variability (increased similarity) among the three ethnic grou ps according to the acrophase profiles. Therefore it is assumed that t he reduction in the variability among the ethnic groups is influenced by the major compatible entraining signals (awakening time, sleep time , and meal time).