Case Report: Exertional rhabdomyolysis in a spin class participant with sickle cell trait.

Exertional rhabdomyolysis is more common in sickle trait due to a predisposition to dehydration and inability to concentrate the urine. Spinning, an indoor cycling workout, has been associated with exertional rhabdomyolysis in recent reports. A consequence of rhabdomyolysis is acute kidney injury, which may be expected to be more common in patients with sickle trait. We report a case of spinning induced rhabdomyolysis in a woman with sickle trait that did not result in renal injury. "Spin rhabdo" is thought to be more severe than other causes of exertional rhabdomyolysis and is associated with higher creatine kinase levels than other causes of exertional rhabdomyolysis. Therefore, individuals with known sickle trait should visit their physician prior to participation in spin classes for the first time. We might also consider voluntary screening for sickle trait in at risk populations prior to enrolling in spin classes given that many patients are unaware of their sickle trait status.

Ciliopathy-associated gene Cc2d2a promotes assembly of subdistal appendages on the mother centriole during cilia biogenesis.

The primary cilium originates from the mother centriole and participates in critical functions during organogenesis. Defects in cilia biogenesis or function lead to pleiotropic phenotypes. Mutations in centrosome-cilia gene CC2D2A result in Meckel and Joubert syndromes. Here we generate a Cc2d2a(-/-) mouse that recapitulates features of Meckel syndrome including embryonic lethality and multiorgan defects. Cilia are absent in Cc2d2a(-/-) embryonic node and other somatic tissues; disruption of cilia-dependent Shh signalling appears to underlie exencephaly in mutant embryos. The Cc2d2a(-/-) mouse embryonic fibroblasts (MEFs) lack cilia, although mother centrioles and pericentriolar proteins are detected. Odf2, associated with subdistal appendages, is absent and ninein is reduced in mutant MEFs. In Cc2d2a(-/-) MEFs, subdistal appendages are lacking or abnormal by transmission electron microscopy. Consistent with this, CC2D2A localizes to subdistal appendages by immuno-EM in wild-type cells. We conclude that CC2D2A is essential for the assembly of subdistal appendages, which anchor cytoplasmic microtubules and prime the mother centriole for axoneme biogenesis.

Identification of a new mutation in the gene coding for hairless protein responsible for alopecia universalis: The importance of direct gene sequencing.

Mutations in the gene HR coding for the hairless protein are associated with atrichia with papular lesions (APL), an autosomal recessive form of alopecia universalis that is characterized by generalized scalp and body atrichia with papular lesions. We here describe a South Italian family of ancient Albanian heritage. The full phenotype with complete atrichia was expressed in 2 siblings, whereas the parents and one sister were unaffected. Direct sequencing of the gene coding for the hairless protein allowed the identification of a new mutation in exon 17. Consistent with the recessive inheritance of the disease, both the siblings were homozygous for the mutation, whereas the parents and the unaffected sister where heterozygous. A relevant discrepancy with a haplotype linkage study is reported, stressing the importance of gene sequencing in genetic diagnosis and counseling because linkage studies can be biased by recombination events.