Sentences with phrase «xy sex»

A group of researchers from Case Western Reserve University School of Medicine have completed a comprehensive molecular analysis of a toddler who developed as a female despite having a male genetic background, termed XY sex reversal.

This mismatch (designated XY sex reversal) prevents the formation of either testes or functional ovaries, a condition often associated with gonadoblastoma, a rare form of cancer.

In most cases, mutations lead to XY sex reversal, a syndrome in which babies are born with a female appearance, including external genitalia, uterus and fallopian tubes.

Not exact matches

Whether a mammal is a male or a female usually comes down to its set of sex chromosomes, either XX if you're female, or XY, male.

In nearly all Lepidoptera — the order that includes moths and butterflies — sex is determined by a WZ chromosome system, in contrast to the XY system used in mammals.

The idea was to use the standard idea of sex determined by sex chromosomes — XX for female and XY for males — and to ask what would happen if culture affected the different numbers of each being produced.

In addition to normal ovarian development, the increased number of gonocytes (fetal and neonatal germ cells) is sufficient for male - to - female sex reversal in XY medaka.

When germ cells are removed in medaka, XX (female) fish show female - to - male sex reversal, while XY (male) fish with excessive germ cells, which is usually associated with egg production, exhibit male - to - female sex reversal.

Such impairment prevents testes development, leading to a mismatch between a child's chromosomal sex (XY, ordinarily male) and outward features (female).

However, the idea may provide an explanation for evidence that XXY men have more sex than men with the regular XY.

With lizards, sex is differentiated in two ways: on the basis of chromosome pairs (XY and ZW) and on the basis of a temperature - sensitive system (which is to say that sex is determined by temperature).

All this leads to the question of how confident you can be that in the period when sex is being determined, the threshold number of XY cells required for sex / testis determination were truly absent in those putative XO organisms?

This chromosomal variation involves their sex chromosomes, ranging from simple systems (XX / XY), with heterochromosomes represented by either micro - or macrochromosomes, to multiple systems (X1X1X2X2 / X1X2Y).

Beatrice Mintz (1968) reported enzyme and kayotype studies showing an adult male sex chromosome chimera with 95 % XX and only 5 % XY somatic cellular components.

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