In situ hybridization analysis of gibbon chromosomes suggests that amplification of alpha satellite DNA in the telomere region is confined to two of the four generaスダラ バイシャルン・ウィスィ アサイタムクン・平井百合子・原暢・古賀章彦・平井啓久 【背景】アルファサテライトＤＮＡは、霊長類のセントロメアの主要なＤＮＡ成分である。テナガザル科のうちのシアマン（Symphalangus 属）で、このアルファサテライトＤＮＡがテロメア領域に大規模に存在することを、先に報告した。
【結果】テナガザル科は、Hoolock, Hylobates, Nomascus, Symphalangus の４つの属から成る。シアマンでみられた現象がどの程度の範囲で起こっているかを、染色体へのハイブリダイゼーションで調べた。Nomascus と
Symphalangus の２属に限定されるであろうとの結果を得た。
【意義】４つの属の系統関係はいまだ不明である。今回得られた結果は、Nomascus と
Symphalangus の２属が近い関係にあり、この２属の共通の祖先でアルファサテライトＤＮＡの増幅が生じたとすると、説明が容易である。 Genome 55 (2012): in press. 
The siamang
Symphalangus syndactylus, a species of the family Hylobatidae (gibbons), carries large blocks of constitutive heterochromatin in the telomere region of chromosomes. We recently found that alpha satellite DNA constitutes these heterochromatin blocks as a main component. Alpha satellite DNA, tandem repeat sequences of 171-bp repeat units, is a major component of centromeres in primates. In addition to siamang, the white-cheeked gibbon
Nomascus leucogenys was previously found to carry the alpha satellite DNA in the telomere region, although not as large a scale as the siamang. Gibbons comprise 4 genera:
Hoolock, Hylobates, Nomascus and Symphalangus. Here we report that the amplification of alpha satellite DNA in the telomere region is probably confined to 2 genera:
Nomascus and Symphalangus. We examined 1 species of Hoolock and 4 species of
Hylobates, and obtained evidence against such an amplification event in these species. The phylogenetic relationship of the 4 gibbon genera remains unclear. One simple explanation for the current distribution of the telomere region alpha satellite DNA would be that
Nomascus and Symphalangus are relatively closely related and the amplification occurred in their common ancestor. OCT/19/2012
Copyright(C) 2012 PRI ( ).
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