[What is the future of our genome?].
Where do we go and what will happen with our genomes? Viewed as a reflection of what we know about our origin as Homo sapiens, history and forecast. Archeogenetics tries to find our sourcing place and to explain how humans occupied the globe. One of the first theories based on mtDNA polymorphisms@ studies stressed on our African origin followed by stepwise dispersal all over the world which took approximately 80,000 years. But not all findings agreed with this assumption if based on nuclear loci and supported multifocal origin of humans. The process of establishing a new species--Homo sapiens, is still not fully understood and many questions remained unanswered. From the point of view of population genetics we can assume that: 1. Mutability (natural or from internal causes) does not change though we cannot neglect suspicion that environment could influence its increase. The content of harming mutations in our genome, due to the protective effect of health care, which blocks natural selection, is increasing and moreover changes of our life style opened the door for manifestation of week deleterious alleles accumulated during foregoing period of evolution. Also prolongation of our life span is accompanied with effects of genotypes positively selected because of their positive effect on our reproductive period but which could be harmful during postreproductive stage--antagonistic pleiotropy. 2. According traditional assumption on the quality of new mutations is that they are either neutral or harming. Changes which are drift-dependent are becoming reduced. 3. Effective population size (steady state could be supposed or some increase due to more intensive local migration). 4. Migration (In spite of absence of corresponding demographic data) seems to be nowadays more intensive than it was in the past.
Brdicka
R
R
Ustav hematologie a krevní transfuze, Praha. rbrdicka@uhkt.cz
Cerný
V
V
D005544:Forecasting; D005828:Genetics, Population / Q000639:trends*; D015894:Genome, Human; D006801:Humans; D008136:Longevity / Q000235:genetics; D009154:Mutation