An RBP family with recent RRM duplications. (A) The members in the human DAZ protein family contain one or more RRMs and DAZ-like domains. All RRMs in DAZ1, DAZ2, DAZ3, DAZ4, and DAZL are identical, whereas the RRM in BOLL has 53% sequence identity with the other RRM. The DAZ1 to DAZ4 are in the Y chromosome, while BOLL and DAZL are in chromosomes 2 and 3. The ortholog genes in other species were identified by a combination of inparanoid annotation and blast search, and species that contain various DAZ proteins were represented with different boxes. The DAZ proteins with multiple RRMs were only found in certain primates. (B) The SNP density of each human DAZ protein was compared with the average density of other genes in the same chromosome. The SNP density ratios between DAZ genes relative to other genes in the same chromosome are indicated. The genes in the Y chromosome encoding DAZ proteins have lower SNP density, suggesting that they are more recently diverged genes.
