FISH mapping of the sex-reversal region on human chromosome 9p in two XY females and in primates.

Accumulating evidence suggests that haploinsufficiency of a dosage-sensitive gene(s) in human chromosome 9p24.3 is responsible for the failure of testicular development and feminisation in XY patients with monosomy for 9p. We have used molecular cytogenetic methods to characterise the sex-reversing 9p deletions in two XY females.

Trisomy 2q35-q37 due to insertion of 2q material into 17q25: clinical, cytogenetic, and molecular cytogenetic characterization.

We present a 7-year-old boy with growth retardation, developmental and mental delay, and minor physical abnormalities. The patient had a male karyotype with duplicated material of unknown origin in the long arm of chromosome 17. The origin of the duplicated material was clarified by fluorescence in situ hybridization.

Microdeletion 22q11 in complex cardiovascular malformations.

Besides DiGeorge, velocardiofacial and conotruncal anomaly face syndromes, some of the isolated congenital heart diseases have also been associated with a chromosomal deletion in 22q11. These disease entities, which had originally been considered to have a different genetic background, are now included in the CATCH-22 microdeletion complex. CATCH 22 is an acronym for cardiac defect, abnormal facies, thymic hypoplasia or aplasia and T-cell deficiency, cleft palate, hypoparathyroidism, and hypocalcemia.

[Clinical and cytogenetic problems in diagnosis of fragile X syndrome].

The fragile X or Martin-Bell syndrome is the second most common chromosomal cause of mental retardation. It has a prevalence of 1:1000; the clinical and psychopathologic symptoms vary. The difficult diagnosis rests on cytogenetic evidence of the fragile site at Xq 27.

[A child with XYY syndrome as experienced by his mother. A report of daily journal recordings].

A mother's experiencing of the development of her son with "XYY syndrome" is presented based on notes from the mother's diary. According to recent findings in unselected longitudinal studies the boy clearly belonged to a subgroup of the more severely affected children. His developmental language and motor delays, other language problems and problems at school were typical, whereas his slightly reduced IQ, in the lower normal range, and aggressive and autistic symptoms were atypical.