One of the most interesting questions of hominin evolution is how much of our vanished cousins remains in us. Between 1-4 percent of the modern human genome is derived from Neanderthals everywhere but sub-Saharan Africa. In addition, between 4-6 percent of the modern Melanesian genome has been shown to be a separate species of archaic hominin, Denisovans. Denisovans and Neanderthals made large-scale, long-term positive contributions to the human genome. interesting place.
Most of the differences in human populations (or differences between archaic and modern hominins) focus on adaptive single-nucleotide variants (SNV). Archaic northwest Europeans the ability to digest lactose, and the ability to do so is a textbook case of human natural selection.
Single nucleotide variations found in the genome of the Tibetan people are associated with greater acclimatization to high-altitude These issues have been discussed in the Denisovan genome.
This new research is not '. t focused on SNVs. Instead, it analyzed the modern Melanesian genome for signs of copy number variants (CNVs). Copy number variation is when the number of copies of an entire gene is different between individuals. Huntington's disease, for example, is a specific sub-section of Huntington's disease. CNVs are much larger than SNVs and they tend to be very selective. Any evidence of conserved CNVs in the Melanesian population that could be traced to the Denisovan or Neanderthal genome would, therefore, be considered that these variants conferred benefits.
of CNVs on the human genome is an active field of study. SNVs have historically received far more attention. The discovery of conserved CNVs in the Melanesian population from archaic Denisovan and Neanderthals is significant in its own right. It's still not clear, however, exactly what variation actually does.
Denisovan and Neanderthal Contributions
The researchers found two specific CNVs – one associated with the Denisovan genome , and one associated with Neanderthals. 79 percent of Melanesians carry a duplication on chromosome 16p11.2 of> 383,000 base pairs (kbp) that originated from Denisovans and what has been introduced into the native population 60,000-170,000 years ago.
The second variation What's special about the Denisovan addition to what it says is about 36 percent of modern melanesians. "It's located on chromosome 8p21.3 and is a 6-kbp deletion and a ~ 38-kbp duplication."
according to the researc denisovan in origin ist part of a locus which "exhibits an enrichment of complex recurrent structural rearrangements, which predicts humans to the second most common genetic cause of autism, accounting for ~ 1% of patients. "
CNV is directly adjacent to the area of chromosomes where genes are known to be associated with autism.
This specific section of the human genome is known to be unstable and prone to breakage errors. Previous research on 16p11.2 has found that an earlier duplicative transposition of the BOLA2 gene some 282,000 years ago
The fact Denisovan contribution to the human genome is 1). Huge 2). Built in the metaphorical swamp of 16p11.2, and 3). Highly conservative suggests it is important to retain. The Neanderthal CNV includes TNFRSF10D (tumor necrosis factor receptor superfamily 10D). According to the researchers, "TNFRSF10D has been expressed as one of the primate-specific genes preferentially expressed in progenitor cells of the human fetal neocortex."
What is it all mean?
Honest answer: Nobody is sure. The researchers theorize that they probably transmitted to their loved ones in an isolated tropical environment.
CNVs originating in archaic hominins and introgressed into modern humans have played source: http://en.wikipedia.org/wiki/National_Primary_Participation_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variable_Variant_Variant_Variant_Variant_Variant_Variable_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variant_Variable_Variant_Variant_Variant_Variant_Variable_Variant_Variant_Variant_Variant_Variant_Variant_ The application of these techniques do for quite some time to come.
Written with assistance from Jessica Hall. Homo sapiens with Homo neanderthalensi s. Credit: Wikipedia.
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