coalescence

Y-chromosome data

Statistical analysis of Y chromosome data have been carried out using coalescent theory devised by Kingman.

Coalescent-based techniques using numerical methods to study complex likelihood functions derived from Bayesian analyses were developed subsequently and have facilitated estimation of key parameters in the Y chromosome genealogy under specific assumptions about demographic history.

Tang et al. have shown that important evolutionary properties of the Y chromosome TMRCA, which is close to 100 kya, can be derived under few demographic assumptions.

Two recent estimates of TMRCA from mtDNA have been made using different methods. From complete mtDNA sequences (excluding the D loop) in a sample of 53 individuals, 516 segregating sites were seen and a TMRCA was estimated at 171 50 kya. From a sample of 179 individuals with 971 SNPs, the TMRCA was estimated at 200−281 kya using a generation time of 25 years, and 160−225 kya using a generation time of 20 years. Corresponding estimates for the NRY-based TMRCA are 60−130 kya and 72−156 kya, with generation times of 25 and 30 years, respectively.

References

 Cavalli-Sforza LL, Feldman MW. The application of molecular genetic approaches to the study of human evolution. Nat Genet. 2003 Mar;33 Suppl:266-75. PMID: 12610536