New chromosomal malformation syndromes. I. Partial monosomy 8p. An attempt to establish a new chromosome deletion syndrome.

A mentally retarded 8-year-old boy with a de novo partial monosomy for the short arm of the No. 8 chromosome is described. Based on G-banding analysis, the patient's karyotype was identified in lymphocytes and skin fibroblasts as 46,XY,del(8) (pter leads to p21:). No chromosomal abnormalities were found in the phenotypically normal mother, father and sister of the propositus. Four further cases described in the literature indicate that partial monosomy of the short arm of the No. 8 chromosome might be associated with a syndrome characterized by the following stigmata: mental retardation, slow growth, high forehead, broad chest, wide-set nipples, pulmonary stenosis with atrial and/or ventricular septal defect, hypoplasia of the genitalia, dermatoglyphic stigmata.