Serial translocation by means of circular intermediates underlies colour sidedness in cattle

Abstract

Colour sidedness is a dominantly inherited phenotype of cattle characterized by the polarization of pigmented sectors on the flanks, snout and ear tips. It is also referred to as 'lineback' or 'witrik' (which means white back), as colour-sided animals typically display a white band along their spine. Colour sidedness is documented at least since the Middle Ages and is presently segregating in several cattle breeds around the globe, including in Belgian blue and brown Swiss. Here we report that colour sidedness is determined by a first allele on chromosome 29 (Cs(29)), which results from the translocation of a 492-kilobase chromosome 6 segment encompassing KIT to chromosome 29, and a second allele on chromosome 6 (Cs(6)), derived from the first by repatriation of fused 575-kilobase chromosome 6 and 29 sequences to the KIT locus. We provide evidence that both translocation events involved circular intermediates. This is the first example, to our knowledge, of a phenotype determined by homologous yet non-syntenic alleles that result from a novel copy-number-variant-generating mechanism.

Pseudoautosomal Region 1 Length Polymorphism in the Human Population

“…The exact mechanism by which insertional translocations are generated remains, however, to be established. Interestingly, Durkin, et al [26] showed that several insertional translocation events in cattle genome evolution have occurred via a circular intermediate which subsequently integrated into the receptor chromosome. Here, we present, to our knowledge, the first example of an insertional translocation which is generated by NAHR.…”

Genomic Insights into the Saccharomyces sensu stricto Complex

“…Subsequent detailed analysis of several industrial S. cerevisiae genomes by Borneman et al (2011) showed that while this cluster of five genes was specific to wine strains (with the exception of the biofuel strain JAY291), it displayed strainspecific differences in copy number, genomic location, and gene order. Diversity in the cluster was shown to be consistent with mobilization into, and throughout, the wine yeast genome as a circular intermediate via an unknown process that has since been proposed to also occur in both mammals and fish (Borneman et al 2011;Fujimura et al 2011;Durkin et al 2012). Subsequent to this work, this genomic feature has been located in the genomes of several additional strains of S. cerevisiae that all seemingly reside in the same wine-specific phylogenic clade (Figure 2A).…”

A Frameshift Mutation in KIT is Associated with White Spotting in the Arabian Camel

“…KIT , v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolo g, is one of the most commonly implicated genes for white spotting phenotypes in animals [17,18,19,20,21,22,23,24]. There are four reported frameshift mutations in the domestic horse, all of which were associated with extensive white spotting [17,25,26].…”