We describe a brother and sister who both had holoprosencephaly, polydactyl
y, cardiac lesions and a normal karyotype. The parents were first cousins a
nd a diagnosis of pseudotrisomy 13 syndrome is suggested. This report provi
des further support that the inheritance of pseudotrisomy 13 syndrome is au
tosomal recessive. Clin Dysmorphol 9: 115-118 (C) 2000 Lippincott Williams
& Wilkins.