Abraham's children in the genomic era
Time and geographic distance have raised the question of whether current Jewish communities around the world share more than a religious background. Here, Atzmon and colleagues tackle this question through their genome-wide analysis of seven distinct contemporary Jewish populations. Comparing the genetic profiles of these Jewish populations with those of non-Jewish people from the same regions, this group is able to identify distinct genetic patterns. While the different Jewish populations can be distinguished genetically, they can also be separated from non-Jewish populations, indicating that contemporary Jews share both religious and genetic history.

Nonrecurrent rearrangements in CMT1A and HNPP
The neuropathies Charcot-Marie-Tooth disease type 1A (CMT1A) and hereditary neuropathy with liability to pressure palsies (HNPP) are caused by genomic rearrangements of 17p12. Although the vast majority of the 17p12 rearrangements are recurrent and due to nonallelic homologous recombination mediated by low-copy repeats, there is a subset of cases that are unique disruptions of atypical size. To learn more about these nonrecurrent rearrangements, Zhang and colleagues characterize the breakpoint sequences in a collection of such cases.

Controlling for population stratification in mtDNA association studies
The wealth of ancestry information contained in mtDNA is often utilized in population studies, but its presence also requires that steps be taken to control for hidden population substructure when mtDNA is used in association studies. A number of methodologies have been developed to handle population stratification (PS) in autosomal data, but less focus has been given to ways to correct for PS when using mtDNA. In this issue, Biffi and colleagues perform a comprehensive analysis of the effects of PS in mtDNA association studies and evaluate the best strategies for controlling it.

A definitive haplotype map of the Asian population
Determining CNV status by using SNP data is often complicated by the diploid and heterozygous character of the human genome; the phase of the SNP data must be inferred in order to establish the nature of the CNVs. Complete hydatidiform moles (CHMs) are a source of DNA that can bypass this issue. CHMs are products of conception in which all the genomic DNA is contributed by a single parent, and the tissue can be homozygous across the genome. In this issue, Kukita and colleagues present their characterization of the CNV structure of CHMs from the Japanese population. Their data are collected to produce a definitive map of the SNP and CNV haplotypes of these samples.

UFS is caused by HPSE2 mutations
Urofacial syndrome (UFS) is an autosomal-recessive disorder characterized by urinary and facial phenotypes. If left untreated, UFS can result in kidney failure. In this issue, Pang and colleagues and Daly and colleagues independently perform homozygosity mapping and sequence analysis on a number of ethnically diverse UFS patients. Both groups identify causative HPSE2 mutations in their patients. This work points to a role for heparatinase 2 in this potentially lethal condition.