Editing Microcephalin (section)

==Evolution==
A derived form of ''MCPH1'' appeared about 37,000 years ago (any time between 14,000 and 60,000 years ago) and has spread to become the most common form of microcephalin throughout the world except [[Sub-Saharan Africa]]; this rapid spread suggests a [[selective sweep]].<ref name = "AutoR3-7"/><ref name = "AutoR3-10"/>  However, scientists have not identified the [[evolutionary pressure]]s that may have caused the spread of these mutations.<ref name = "AutoR3-11"/>  This variant of the gene is thought to contribute to increased brain volume<ref>{{cite journal | vauthors = Lari M, Rizzi E, Milani L, Corti G, Balsamo C, Vai S, Catalano G, Pilli E, Longo L, Condemi S, Giunti P, Hänni C, De Bellis G, Orlando L, Barbujani G, Caramelli D | title = The microcephalin ancestral allele in a Neanderthal individual | journal = PLOS ONE | volume = 5 | issue = 5 | pages = e10648 | date = May 2010 | pmid = 20498832 | pmc = 2871044 | doi = 10.1371/journal.pone.0010648 | bibcode = 2010PLoSO...510648L | doi-access = free }}</ref> and may correlate with the incidence of [[tonal language]]s,<ref name = "AutoR3-9"/> though modern distributions of [[chromosome]]s bearing the ancestral forms of ''MCPH1'' and ''[[ASPM (gene)|ASPM]]'' showed neither microcephalin or ASPM had any significant effect on [[IQ]].<ref name="AutoR3-11"/>

The derived form of ''MCPH1'' may have originated from a lineage separated from modern humans approximately 1.1 million years ago and later introgressed into humans. This finding supports the possibility of [[Archaic human admixture with modern humans|admixture between modern humans and extinct ''Homo'' spp]].<ref name = "AutoR3-10"/> While [[Neanderthal]]s have been suggested as the possible source of this haplotype, the haplotype was not found in the individuals used to prepare the first draft of the Neanderthal genome.<ref name = "Human genome tales"/><ref name = "green"/>