Reviews & Analysis

Until very recently, it was widely touted that the complete DNA sequences of any two human beings were 99.9% identical. A new study refutes this notion through a comprehensive comparison of two individual genomes which detects hundreds of new structural genomic variants.

The spindle checkpoint delays the cell cycle when chromosomes are not properly attached to the mitotic or meiotic spindle, giving cells time to correct the error. A new study now strengthens the connection between checkpoint failure and human aneuploidies by showing that the spindle checkpoint component Mad3p is required for accurate segregation of meiotic chromosomes that have not recombined with each other.

Yeast's ability to produce ethanol in high concentrations has been exploited by humans for millennia. Two recent papers help us to understand the genetic changes that made this species so appealing to humans and the history of its domestication.

Single-sperm genotyping has provided evidence for hot spots of locally intense recombination in humans. Previous efforts have shown that statistical methods can identify these hot spots as local deficits of linkage disequilibrium, but a report in this issue shows that some recombination hot spots leave no signature of reduced linkage disequilibrium.

The restriction of herpesvirus by natural killer cells, initiated before the acquired immune response, illustrates the value of innate immune mechanisms for viral containment. Now, a new study shows that the activating natural killer cell receptor Ly49P and the major histocompatibility complex class I H-2D^k molecule act in concert to restrict mouse cytomegalovirus infection, identifying a new mechanism of host resistance.

Maternal hypertension in pregnancy is a genetically complex condition originating in the placenta. Because of imprinting, only the maternal copy of the gene encoding STOX1 is expressed in invasive placental extravillous trophoblasts. Therefore, maternally inherited missense mutations affecting this putative DNA-binding protein predispose to preeclampsia, possibly by interfering with differentiation of the trophoblast cells.

A microarray-based study of the nematode Caenorhabditis elegans offers a first glimpse of the effect of mutation accumulation on transcriptional variation. One major conclusion is that stabilizing selection must constrain the divergence of gene expression profiles in natural populations.

Inversin is a component of a poorly understood cilia-based mechanism responsible for specifying the left-right axis during development and for maintaining normal kidney architecture throughout life. A new study now suggests that inversin might act as a flow-regulated molecular switch between canonical and noncanonical Wnt pathways, providing insights into the mechanisms underlying cilia-based signaling processes.