4p trisomy secondary to paternal translocation t(4p-;15q+)

A new case of trisomy 4p is reported. The patient was a boy with dysmorphism, growth failure and developmental retardation. Craniofacial features included microcephaly with a flat forehead, a prominent glabella, hyperteleorism, a broad, concave nasal bridge, a bulb-shaped nose, a wide mouth with a prominent upper lip and a short philtrum, low-set ears, a low hairline, micrognathia, and a short neck. Abdominal muscles were normal. Cryptorchidism with a hypoplastic scrotum and a micropenis were found, as well as forced flexion of the fingers and talipes equinus. The intravenous urogram disclosed ptosis of the right kidney. Developmental retardation was severe with an IQ under 50. RHG banding techniques on peripheral lymphocytes disclosed 4p14 pter duplication. The karyotype was 46,XY inv dup(4-p) (p14----pter). The mother's karyotype was normal. The father had a translocation between the short arm of chromosome 4 and the long arm of chromosome 15; his karyotype was 46,XY, t(4;15) (p14;q26). Thus, the child had trisomy for a segment of the short arm of chromosome 4 (p14----pter) and monosomy for the terminal band of the long arm of chromosome 15 (15q26). The first case of trisomy 4p was reported in 1970 by Wilson et al. Since then, there have been 46 additional reports in the medical literature. Although children with trisomy 4p share a number of features, the phenotypic manifestations of this chromosomal abnormality are variable and nonspecific, making clinical diagnosis difficult.