Target article:
Green, R.E., Krause, J., Briggs, A.W., Maricic, T., Stenzel, U., Kircher, M. et al. (2010). A draft sequence of the Neandertal genome. Science, 328, 710-722.
This study created a draft sequence of approximately 60% of the Neanderthal genome based on nucleotides from three individual Neanderthal samples (Vindija Neanderthal fossils Vi33.16, Vi33.25 and Vi33.26). The study differs from previous attempts to examine Neanderthal DNA as it examines mitochondrial DNA, Y chromosomal DNA and nuclear DNA using the 454 platform which allows for less contamination with DNA from researchers than amplification using conventional PCR. This sequence was then compared to the genomes of eight present-day humans from different geographical regions. …show more content…
The samples from early modern humans were used so as to distinguish between endogenous human DNA and contamination from present day DNA. The mDNA derived from the Neandertals was similar to those found in earlier studies on specimens from the same region (Krings et al, 2000; Ovchinnikov et al, 2000; Schmitz et al, 2002). None of the mDNA derived from early humans however was found to be similar to the Neanderthal mDNA. Serre et al. (2004) conclude that this suggests there was no significant genetic contribution of Neanderthal DNA to early modern humans. They however acknowledge that their study was constrained by the limited number of samples with appropriately preserved DNA and by the fact that mitochondrial DNA is inherently sex linked. They thus theorised that Neandertals may have possible contributed a small number of genes to contemporary humans, which may have been lost to genetic drift.
Ghirotto, S., Tassi, F., Benazzo, A. & Barbujani, G. (2011). No evidence of Neandertal admixture in the mitochondrial genomes of early European modern humans and contemporary Europeans. American journal of physical anthropology, 146, …show more content…
(2010)’s proposal of admixture between anatomically modern humans and Neandertals and the identification of Neanderthal ancestry at specific loci, this study identified a number of Neanderthal haplotypes in 1,004 contemporary humans. They found that some biological pathways, for instance alleles associated with the production of keratin, were augmented in those with Neanderthal ancestry in European and East Asian populations. Sankararaman et al. (2014) propose that Neanderthal genes may have helped anatomically modern humans adapt to non-African environments. The study also found that a number of Neanderthal derived alleles are associated with diseases including type 2 diabetes, lupus and Crohn syndrome. “Deserts” of Neanderthal alleles in certain regions, particularly on the X chromosomes and genes that express in the testes, indicate that Neanderthal derived alleles may result in the sterility in males amongst modern humans. Furthermore, the authors theorise that negative selection may explain the higher frequency of Neanderthal derived genes in East Asians in comparison to Europeans. This theory would be particularly applicable if East Asian populations were smaller than European populations resulting in less efficient selection to remove ineffective Neanderthal
Green, R.E., Krause, J., Briggs, A.W., Maricic, T., Stenzel, U., Kircher, M. et al. (2010). A draft sequence of the Neandertal genome. Science, 328, 710-722.
This study created a draft sequence of approximately 60% of the Neanderthal genome based on nucleotides from three individual Neanderthal samples (Vindija Neanderthal fossils Vi33.16, Vi33.25 and Vi33.26). The study differs from previous attempts to examine Neanderthal DNA as it examines mitochondrial DNA, Y chromosomal DNA and nuclear DNA using the 454 platform which allows for less contamination with DNA from researchers than amplification using conventional PCR. This sequence was then compared to the genomes of eight present-day humans from different geographical regions. …show more content…
The samples from early modern humans were used so as to distinguish between endogenous human DNA and contamination from present day DNA. The mDNA derived from the Neandertals was similar to those found in earlier studies on specimens from the same region (Krings et al, 2000; Ovchinnikov et al, 2000; Schmitz et al, 2002). None of the mDNA derived from early humans however was found to be similar to the Neanderthal mDNA. Serre et al. (2004) conclude that this suggests there was no significant genetic contribution of Neanderthal DNA to early modern humans. They however acknowledge that their study was constrained by the limited number of samples with appropriately preserved DNA and by the fact that mitochondrial DNA is inherently sex linked. They thus theorised that Neandertals may have possible contributed a small number of genes to contemporary humans, which may have been lost to genetic drift.
Ghirotto, S., Tassi, F., Benazzo, A. & Barbujani, G. (2011). No evidence of Neandertal admixture in the mitochondrial genomes of early European modern humans and contemporary Europeans. American journal of physical anthropology, 146, …show more content…
(2010)’s proposal of admixture between anatomically modern humans and Neandertals and the identification of Neanderthal ancestry at specific loci, this study identified a number of Neanderthal haplotypes in 1,004 contemporary humans. They found that some biological pathways, for instance alleles associated with the production of keratin, were augmented in those with Neanderthal ancestry in European and East Asian populations. Sankararaman et al. (2014) propose that Neanderthal genes may have helped anatomically modern humans adapt to non-African environments. The study also found that a number of Neanderthal derived alleles are associated with diseases including type 2 diabetes, lupus and Crohn syndrome. “Deserts” of Neanderthal alleles in certain regions, particularly on the X chromosomes and genes that express in the testes, indicate that Neanderthal derived alleles may result in the sterility in males amongst modern humans. Furthermore, the authors theorise that negative selection may explain the higher frequency of Neanderthal derived genes in East Asians in comparison to Europeans. This theory would be particularly applicable if East Asian populations were smaller than European populations resulting in less efficient selection to remove ineffective Neanderthal