Short rib-polydactyly syndrome (SRPS) with anencephaly and other central nervous system anomalies: a new type of SRPS or a more severe expression of a known SRPS entity?

We describe two patients with short rib-polydactyly syndrome (SRPS) from two unrelated Spanish families. These patients present clinical and radiological characteristics that overlap those of the different established types of SRPS. In addition, one patient had anencephaly and the other patient had severe brain abnormalities with a family history of an older sister with anencephaly, and a brother diagnosed with SRPS. This second family is interesting in that the two affected brothers present with different clinical and radiological findings; for example, one had ovoid tibiae and the other did not. This particular family shows that intrafamiliar variation is also observed within SRPS. It remains unsettled whether these cases might be considered a new type of SRPS or a variant of an established entity or whether the differences between the SRPS represent variability or heterogeneity. Molecular studies may answer this question in the near future.