A Chromosomal Break and Partial Delection of a Number 9 Chromosome

Abstract

A male infant was observed with a complex of un usual clinical abnormalities. Chromosomal studies revealed that the child was mosaic for a chromosomal fragment from the long arms of a number 9 chromosome. The majority of cells contained 46 chromosomes with a partially deleted number 9 chromosome and a chromosomal fragment. From these data and others repor ted, it would appear that there is a susceptibility for breakage of the long arms of the number 9 chromosome at the junction of the heterochromatin and euchromatin area closest to the centromere. The lymphocytes from this child are capable of transformation into long-term lymphocyte cultures, and after many months in culture the chromosomal fragment has replicated in the cultured cells even though it contained no detectable centromere.

Cloacal exstrophy in an infant with 9q34.1‐qter deletion resulting from a de novo unbalanced translocation between chromosome 9q and Yq

“…Interestingly, our patient presented with a pure terminal 9q34.1‐qter deletion, resulting from a de novo translocation between chromosome 9q34.1 and the heterochromatin region of chromosome Y. A review of the literature revealed 14 observations of pure partial 9q deletion with variable breakpoints [Newton et al, 1972; Smith et al, 1973; Jenkins et al, 1976; Wisniewski et al, 1977; Turleau et al, 1978; Ying et al, 1982; Schinzel, 1988; Farrell et al, 1991; Park et al, 1991; Pfeiffer et al, 1991; Schimmenti et al, 1994; Shimkets et al, 1996; Ayyash et al, 1997; Kleyman et al, 1997]. Only three of them included 9q34.1‐qter region [Schimmenti et al, 1994; Ayyash et al, 1997; Kleyman et al, 1997] and no characteristic phenotype emerged (Table I).…”

An interstitial deletion of chromosome 9 in a girl with multiple congenital anomalies.

“…With the exception of ring chromosomes, only two other cases of long arm deletion have been reported. The patient of Smith et al (1973) had unusual facies, lumbosacral myelomeningocele, dilatation of the ventricles, upward slanting of the palpebral fissures, a heart murmur, bilateral talipes equinovarus, partial malrotation of the bowel, and urogenital abnormalities. A very confusing cytological picture emerged for this patient, a deletion of two-thirds of the long arm and the presence of one or two presumably related fragments.…”

“…Alfi et al (1976) have studied 6 patients with deletions of the short arm distal to 9p22 and have found consistency in the resulting clinical malformations. Smith et al (1973) reported a unique long arm deletion with associated persistent fragments in a severely malformed boy. In this case, specific identification of the deleted material was difficult.…”

A case of partial monosomy for the long arm of the no. 9 chromosome.

“…9 chromosome were rather rare at present in the literature. Smith et al (1973) reported a case with a chromosomal break and partial deletion of the no. 9 chromosome.…”