A male infant with holoprosencephaly, associated with ring chromosome 21

An infant with holoprosencephaly and a karyotype 46,XY,r(21) is reported. No distinctive craniofacial features suggesting holoprosencephaly were present in this infant who presented with epilepsy, microcephaly and scoliosis with hemivertebra Th 10. This is the first report which links deletion of chromosome 21q to the holoprosencephaly phenotype.