First Trimester Diagnosis of Holoprosencephaly Secondary to a Ring Chromosome 7
Cytogenetic and molecular analysis of ring chromosome 7. Partial karyotype showing the normal chromosome 7 and r(7) (p22.3q36.1) (inset). Ideogram illustrating the 9.7 Mb deleted region defined by aCGH (red bar) and UCSC Genome Browser display of OMIM genes within the deletion (GRCh37/hg19). Known disease-causing genes, including SHH and MNX1, are represented by darker bars.