Fluorescence activated sorting of chromosomes from 49,XXXXY human lymphoblasts has been used to obtain DNA enriched for the human X. This DNA was cloned in lambda phage Charon 21A to obtain a library of approximately 60,000 pfu. Phage inserts free of human highly repeated DNA sequences are localized to different regions of the human X by two independent hybridization analyses. The first utilize...

The human sex-linked genes RPS4X and RPS4Y encode distinct isoforms of ribosomal protein S4. Insufficient expression of S4 may play a role in the development of Turner syndrome, the complex human phenotype associated with monosomy X. In mice, the S4 protein is encoded by an X-linked gene, Rps4, and is identical to human S4X; there is no mouse Y homolog. We report here the organization of the hu...

Two patients with the XXXXY syndrome are presented. Both boys are mentally retarded with short stature, muscular hypotonia, and hypogonadism. A constant feature of this syndrome is a varying degree of epiphysial dysplasia probably secondary to hypotonia and growth deceleration.

We present a pair of dizygotic twins with different abnormal karyotypes. The chromosome anomaly is a sexual aneuploidy in both cases: 48,XXXXY in one, 47,XXY in the second. The origin of the chromosomal anomaly and the hypothetical relation between sexual aneuploidy and twinning is discussed. It is concluded that further studies in twins are necessary to prove the not yet solved problems of non...

Klinefelter syndrome (KS) is characterized in adults by the combination of a tall stature, small testes, gynecomastia, and azoospermia. This case is described in a North African population of the Mediterranean region of North Africa. We report the case of a male 16 years old, of Arab ethnic origin, and diagnosed with this syndrome, who had a small height in relation to a growth hormone (GH) def...