title: Evolutionary breakpoints in the gibbon suggest association between cytosine methylation and karyotype evolution.
abstract: Gibbon species have accumulated an unusually high number of chromosomal changes since diverging from the common hominoid ancestor 15-18 million years ago. The cause of this increased rate of chromosomal rearrangements is not known, nor is it known if genome architecture has a role. To address this question, we analyzed sequences spanning 57 breaks of synteny between northern white-cheeked gibbons (Nomascus l. leucogenys) and humans. We find that the breakpoint regions are enriched in segmental duplications and repeats, with Alu elements being the most abundant. Alus located near the gibbon breakpoints (<150 bp) have a higher CpG content than other Alus. Bisulphite allelic sequencing reveals that these gibbon Alus have a lower average density of methylated cytosine that their human orthologues. The finding of higher CpG content and lower average CpG methylation suggests that the gibbon Alu elements are epigenetically distinct from their human orthologues. The association between undermethylation and chromosomal rearrangement in gibbons suggests a correlation between epigenetic state and structural genome variation in evolution.
authors: Children's Hospital and Research Center Oakland, Oakland, California, United States of America. lcarbone@chori.org
authors: Lucia
authors: L
authors: Carbone
authors: R Alan
authors: RA
authors: Harris
authors: Gery M
authors: GM
authors: Vessere
authors: Alan R
authors: AR
authors: Mootnick
authors: Sean
authors: S
authors: Humphray
authors: Jane
authors: J
authors: Rogers
authors: Sung K
authors: SK
authors: Kim
authors: Jeffrey D
authors: JD
authors: Wall
authors: David
authors: D
authors: Martin
authors: Jerzy
authors: J
authors: Jurka
authors: Aleksandar
authors: A
authors: Milosavljevic
authors: Pieter J
authors: PJ
authors: de Jong
mesh_terms: D020087:Alu Elements; D000818:Animals; D002874:Chromosome Mapping; D003596:Cytosine / Q000378:metabolism*; D053960:DNA Breaks; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D019143:Evolution, Molecular; D015321:Gene Rearrangement; D015894:Genome, Human; D006801:Humans; D006922:Hylobates / Q000235:genetics* / Q000378:metabolism; D007621:Karyotyping; D008957:Models, Genetic; D013045:Species Specificity; D026801:Synteny
chemical_list: D003596:Cytosine