Disease with characteristics of intrauterine and postnatal growth retardation, microcephaly, facial dysmorphism, skeletal dysplasia, low-birth weight and brain anomalies. Although microcephalic osteodysplastic primordial dwarfism (MOPD) types 1 and 3 were originally described as two separate entities on the basis of radiological criteria (notably small differences in pelvic and long bone structure), later reports confirmed that the two forms represent different modes of expression of the same syndrome. Although the causative gene remains unknown, homozygosity mapping has allowed identification of a candidate gene region on chromosome 2q (2q14.2-q14.3). Histological studies suggest that MOPD types 1 and 3 result from a basic defect in cell proliferation and tissue differentiation. Transmitted as autosomal recessive trait.