RESUMEN
We examined the meiotic segregation pattern of a t(1;4)(p36.2;q31.3) reciprocal translocation in two male cousins heterozygous for the translocation. The wife of subject 1 had four recognized spontaneous abortions and two carrier daughters, and the wife of subject 2 had three recognized spontaneous abortions and no live-born children. The results showed that subject 1 had an imbalance rate of 54% and subject 2 had an imbalance rate of 61% with respect to the translocation. This was not statistically different (P = 0.3174) and the 95% confidence intervals overlapped for each segregation type. The sex ratio of X- and Y-bearing sperm was not statistically different than the expected 50%. The rate of structural abnormalities was 11.3% in subject 1 and 17.8% in subject 2. Both of these values were above the range of control subjects in our lab, but only subject 2's value fell outside the 95% confidence interval for the control population.
Asunto(s)
Cromosomas Humanos Par 1 , Cromosomas Humanos Par 4 , Translocación Genética/genética , Aborto Habitual/genética , Adulto , Femenino , Heterocigoto , Humanos , Masculino , Meiosis/genética , Linaje , EmbarazoRESUMEN
Sperm chromosome studies were performed in seven males. One of them had a history of exposure to lysergic acid (LSD) although he was free of the drug for 1 year before the study began. Sixteen ejaculates provided a total of 555 fully analyzable sperm cells. The overall frequency of hyperhaploid sperm cells was 2% and that of structural abnormality 3.6%. The most common structural abnormality was chromosome breaks followed by small chromosome fragments of unknown origin. Three chromosome breakpoints, 10q25, 2q21, and 9q21, were involved twice in different chromosome or chromatid type aberrations. Two of these, 10q25 and 2q21, correspond to chromosomal locations known as common fragile sites.
