Localization of male determining factor on short arm of Y chromosome Case report of a baby with 46, x, t (Yp+;14q‐)

Y chromosome variation has been studied in three groups of Norwegian males: 35 boys from an adolescent psychiatric hospital; 45 men from a hospital for hard‐to‐manage or dangerous, psychotic men; and 26 boys from two ordinary school classes. Y chromosomes with 1, 2, and 3 brightly fluorescing bands were found in all three groups. One boy carried a Y with no bands. The mean values of the Yf/Yq ratio were not significantly different in the three groups (Yf is the length of the distal, brightly fluorescing part of Yq). Two cases of XY/XYY mosaicism were found among the psychotic men. The study shows that the human species is polymorphic with regard to the size of the Y chromosome, i. e. the number of fluorescent bands in the long arm. No phenotypical manifestation of this polymorphism, particuIarly as regards behaviour, was found.

Section: Discussionmentioning

confidence: 99%

No evidence for a correlation between behaviour and the size of the Y chromosome

Brøgger

Urdal

Larsen³

et al. 1977

“…In man, the Y chromosome is necessary both for male differentiation and for normal fertility. The neccssary genes for male differentiation seem to be located on the short arm of the Y (Jacobs & Ross 1966) and more precisely on the centromeric portion of the short arm (Krmpotic et al 1972); it is not known where "fertility genes" could be situated.…”

Section: B Short Y and Other Structural Variationsmentioning

confidence: 99%

Chromosomes and human infertility. I. Mitotic and meiotic chromosome studies in 202 consecutive male patients

Koulischer

Schoysman

1974

Universiteit van Brussel, H6pital Universitaire Brugmann, Brussels, Belgium Mitotic and meiotic chromoqome studies in 202 consecutive infertile male patients are reported. From our rnults and those available from the literature, the following conclusions can be drawn. 1. Mitotic chromosome analysis definitely must be included in the laboratory investigations of male infertility; meiotic studies are recommended, especially in patients with a normal somatic karyotype and unexplained low sperm counts.2. About 10 % of all patients attending male infertility clinics show a mitotic chromosome abnormality: 6-7 % present a Klinefelter's syndrome or its variants, 1-3 have morphological rearrangements of the Y, or sex chromosome mosaicism, and 1-3 % present structural autosome rearrangements (translocations, minor variants, etc.). Decreasing sperm counts are associated with an increaqing probability of aneuploidy. 3.At present, identified meiotic abnormalities could explain about 2 % of male sterilkies in patients with apparently normal somatic chromosomes.

“…Structural abnormalities included in mosaic karyotypes or not identified by special banding techniques have been excluded. Krmpotic et al (1972) described a male infant with some congenital malformations which, except for undescended testes, did not affect internal or external genital organs. The child expired on the sixth day of life.…”

Section: B U U K E I L O N H a L B R E C H T K O M L O S A N mentioning

confidence: 99%

Isochromosome Y [46, X, i(Yq)] and female phenotype

Böök

Eilon²,

Halbrecht³

et al. 1973

A 26‐year‐old patient with female phenotype and the karyotype 46, x, i (Yq) is described. She had no breast, and a rudimentary uterus and streak gonads were present. Apart from a rather deep voice, no signs of masculinization were observed, nor did she display any of the stigmata usually associated with Turner's syndrome. The Yq chromosome was identified conclusively by the Giemsa C‐banding technique. The function of the Y chromosome is discussed briefly, and it is concluded that the factors determining or regulating somatic male differentiation must be located in the short arm of the Y chromosome.