The Wiedemann-Beckwith syndrome in four sibs including one with associated congenital hypothyroidism.

Two boys and two girls from a sibship of six, affected with the Wiedemann-Beckwith syndrome (WBS), are reported. One of the patients also had congenital hypothyroidism, an association hitherto undescribed and possibly fortuitous. Neither stigmata of WBS in other family members nor parental consanguinity were found, indicating a possible autosomal dominant inheritance comprising either a delayed mutation of an unstable premutated gene or non-penetrance.