| A developmental defect with manifestation of variable intramembranous ossification defects of the parietal bones, which is asymptomatic, symptomatic or associated with other pathologies. A congenital disorder caused by insufficient ossification around the parietal notch. In most cases this results from heterozygous loss of function mutations in human homeobox genes, MSX2 (5q35.2) and ALX4 (11p11.2), which encode transcription factors involved in skeletal development. Transmission is autosomal dominant with high but incomplete penetrance. |
