In patients with structural aberrations of the sex chromosomes a direct relation has been found between the phenotype and the extent and site of sex chromosomal deletion (Ferguson-Smith, 1965,1969). Women with deletion of the short arm of the X chromosome invariably have short stature and streak gonads, and usually have several of the other malformations of Turner's syndrome, while those whoseX...

Specimens of Hoplias malabaricus from Lagoa Carioca, an isolated lake of the Rio Doce State Park (state of Minas Gerais, Brazil), were cytogenetically studied. The diploid number was found to be constant, i.e., 2n = 42 chromosomes, although two karyotypic forms were found: karyotype A, characterized by 22M + 20SM chromosomes, observed only in a male specimen, and karyotype B, characterized by 2...

We report here two cases of men, aged 46 and 23 years, with refractory chronic venous leg ulcers in association with sex chromosome aberrations: one with a 47,XXY/48,XXXY karyotype (Klinefelter syndrome) and the other with a 47,XYY karyotype (Jacob syndrome). In both patients, the occurrence of leg ulcers was the reason for seeking medical care; their medical history was other-wise unremarkable...

In patients with structural aberrations of the sex chromosomes a direct relation has been found between the phenotype and the extent and site of sex chromosomal deletion (Ferguson-Smith, 1965,1969). Women with deletion of the short arm of the X chromosome invariably have short stature and streak gonads, and usually have several of the other malformations of Turner's syndrome, while those whoseX...

INTRODUCTION Female sex workers (FSWs) are at high risk of HIV infection. Our objective was to determine the proportion of HIV prevalence in the general female adult population that is attributable to the occupational exposure of female sex work, due to unprotected sexual intercourse. METHODS Population attributable fractions of HIV prevalence due to female sex work were estimated for 2011. A...

Sex determination in major vertebrate groups appears to be very variable, including systems of male heterogamety, female heterogamety and a variety of genetic and environmental sex determining systems. Yet comparative studies of sex chromosomes and sex determining genes now suggest that these differences are more apparent than real. The sex chromosomes of even widely divergent groups now appear...

Experimental and field studies of different turtle species suggest that moisture influences embryonic development and sex ratios, wetter substrates tend to produce more males, and drier substrates produce more females. In this study, we used Trachemys scripta elegans to test the effect of moisture on embryonic development and sex ratios. T. s. elegans eggs were incubated under different tempera...

Sex determination in Drosophila depends on X-linked 'numerator' genes activating early Sex-lethal (Sxl) transcription in females. One numerator gene, sisterless-b (sis-b), corresponds to the achaete-scute (AS-C) T4 basic-helix-loop-helix (bHLH) gene. Two other closely related AS-C bHLH genes, T3 and T5, appear not to function as numerator elements. We analyzed endogenous AS-C expression and sho...

Female patients with a sex chromosome abnormality may be fertile. In patients with a 47,XXX cell line there appears to be an increased risk of a cytogenetically abnormal child but the extent of this risk cannot yet be determined; it is probably lower in the non-mosaic 47,XXX patient than the mosaic 46,XX/47,XXX one. Patients with a 45,X cell line rarly become pregnant, and when they do they app...

Recent analyses of the chromosomal regions that determine male development in sticklebacks and medaka have revealed several features associated with incipient Y chromosome evolution, including suppressed crossing over and the accumulation of repetitive DNA.