CONTEXT 45,X/46,Xidic(Y) mosaicism demands careful and thorough study because of both its variable clinical features and its potential complications. CASE REPORT The present case relates to a three-year-old girl with the mosaic karyotype 46,X,idic(Y)(q11.2)[23]/45,X[6]. She had no signs of virilization or Turner's syndrome phenotype, but she was referred to our hospital because she presented ...

The determination of a baby’s sex begins at the chromosomal level with the insemination of the ovum. Further sexual differentiation follows during the subsequent embryogenesis. However, chromosomal anomalies, gene mutations, and other exogenous or endogenous factors can cause disorders of sexual differentiation. These disorders manifest during childhood or at the latest in puberty, making patie...

The Sex combs reduced (Scr) gene specifies the identities of the labial and first thoracic segments in Drosophila melanogaster. In imaginal cells, some Scr mutations allow cis-regulatory elements on one chromosome to stimulate expression of the promoter on the homolog, a phenomenon that was named transvection by Ed Lewis in 1954. Transvection at the Scr gene is blocked by rearrangements that di...

Fanconi anemia (FA) is a condition that induces susceptibility to bone marrow failure, myelodysplastic syndrome (MDS), and leukemia. We report on a high incidence of expanding clonal aberrations with partial trisomies and tetrasomies of chromosome 3q in bone marrow cells of 18 of 53 FA patients analyzed, detected by conventional and molecular cytogenetics. To determine the clinical relevance of...

When XX germ cells develop in a testis they become spermatogenic. Thus, somatic signals determine the sex of genetically female germ cells. In contrast, XY germ cells experimentally transferred to an ovary do not differentiate oogenic cells. Because such cells show some male characteristics when analyzed in adults, it was assumed that XY germ cells autonomously become spermatogenic. Recently, h...

Triple X syndrome 47XXX is a sex chromosome abnormality characterized by presence of an extra X chromosome. Most of the girls born with triple X chromosomes have no signs or symptoms at birth. The condition often remains undiagnosed until adulthood when the genetic defect is discovered on investigation for other reasons as in this case of a young girl who presented with primary amenorrhoea. Cli...

A family with proximal radioulnar synostosis segregating in three generations is described. Familial radioulnar synostosis is a rare anomaly; however, the sporadic form is a frequent feature in cases of sex chromosome abnormalities and other syndromes. This disorder has been reported in several ethnic groups, but this is apparently the first example from the black population.

Of prime importance in evolutionary biology are the description of pattern and explanations of process. Frequently, however, multiple processes can explain a given pattern. Such cases require experimental protocols or research criteria to distinguish among alternatives so pattern can be critically assigned to process. Noteworthy examples of this approach include evaluating adaptations and ident...

We have isolated three female-specific lethal mutations at the gene Sex-lethal (Sxl): Sxlfb, Sxlfc and Sxlfd. We have carried out the complementation analysis between these mutations and other previously reported Sxlf mutations. It is possible to classify the alleles tested in this report into two complementation groups: the bc group defined by Sxlfb, and Sxlfc, and the LS group defined by Sxlf...

oculo-auriculovertebral dysplasia (goldenhar) is a congenital syndrome. its phenotype differs from craniofacial anomalies to cardiac, vertebral or central nervous system defects. this syndrome is rare and its etiology is not apparent yet. pericentric inversion of chromosome 9 is one of the most common structural balanced chromosomal aberrations with its incidences 15% to 25%. herein we present ...