Spatiotemporal expression in mouse brain of Kiaa2022, a gene disrupted in two patients with severe mental retardation.

We previously identified an inactivating disruption of the X-linked KIAA2022 gene by a chromosomal rearrangement in two male patients with severe mental retardation. In order to determine if KIAA2022 has a role during the development of the central nervous system, we have cloned its murine ortholog, Kiaa2022, determined its genomic structure and studied its expression during mouse development. We show that Kiaa2022 is preferentially expressed in the central nervous system and that the transcript is highly expressed in postmitotic neurons.

Truncation of NHEJ1 in a patient with polymicrogyria.

Polymicrogyria (PMG) is a common malformation of the human cerebral cortex for which both acquired and genetic causes are known. Although genetic heterogeneity is documented, only one gene is currently known to cause isolated PMG. To clone new genes involved in this type of cerebral malformation, we studied a fetus presenting a defect of cortical organization consisting of a polymicrogyric cortex and neuronal heterotopia within the white matter.

Mutation in the 5' alternatively spliced region of the XNP/ATR-X gene causes Chudley-Lowry syndrome.

The Chudley-Lowry syndrome (ChLS, MIM 309490) is an X-linked recessive condition characterized by moderate to severe mental retardation, short stature, mild obesity, hypogonadism, and distinctive facial features characterized by depressed nasal bridge, anteverted nares, inverted-V-shaped upper lip, and macrostomia. The original Chudley-Lowry family consists of three affected males in two generations. Linkage analysis had localized the gene to a large interval, Xp21-Xq26 and an obligate carrier was demonstrated to have highly skewed X inactivation.