Margery W. Shaw

TWO XY SIBLINGS WITH GONADAL DYSGENESIS AND A FEMALE PHENOTYPE.

ANOMALOUS sexual development has been attributed to hormonal imbalance, chromosomal aberration and developmental disturbance of unknown etiology as well as genetic causes such as testicular feminiz...

Minute Y chromosome in the lizard genus Uta (family Iguanidae)

Evidence is presented for an XX/XY sex-determining mechanism in five species of the genus Uta . All species examined have a somatic diploid complement of 12 macrochromosomes and 22 m

Autoradiographic studies of the human Y chromosome

An autoradiographic analysis (using continuous labeling with tritiated thymidine) was made on 317 cells from four normal males. The labeling pattern of the Y chromosome was compared to the first and the last chromosomes to complete replication as well as to G21–22. The Y chromosome was never found to be the last chromosome in the cell to complete replication. Instead, it completed DNA synthesis relatively early (usually among the first 10 chromosomes) but had a distinctively heavy label during the earliest stages of late-S. In 51% of those cells with one labeled G+Y chromosome, a G21–22 was labeled and the Y was not.—It was concluded, therefore, that the human Y chromosome is not a “late-replicating” chromosome but terminates replication earlier than most of the autosomes. In addition, the Y chromosome cannot be distinguished from the G chromosomes on the basis of a consistent and differential labeling pattern.

Chromosome number in the lizard genus Uta (family Iguanidae)

A chromosome number of 34 (12 macro- and 22 microchromosomes) was found to be characteristic of the bone marrow in 47 animals including males from the species Uta antiquus, and both males and females from the following species and subspecies: Uta stansburiana stansburiana, Uta stansburiana stejnegeri, Uta stansburiana elegans, Uta stansburiana klauberi, Uta stansburiana mannophorus, Uta nolascensis, Uta palmeri, and Uta squamata. — Diploid chromosome numbers of 34 and haploid numbers of 17 were found in the nine testis smears examined. — The presence of a large number of hypodiploid figures in the bone marrow smears is attributed to cell fragmentation and the problem of distinguishing the small microchromosomes. — Series of polyploid figures whose chromosome numbers increased in arithmetic rather than geometric progressions were observed in the testis dry smears. Possible alternatives for the origin of these figures are presented. — Problems encountered in the use of chromosome number as a taxonomic character are discussed.

Chromosomes of Peromyscus (Rodentia, Cricetidae)

A karyotypic and autoradiographic study was undertaken in an effort to identify the Y chromosome in five subspecies of the deer mouse, Peromyscus maniculatus . Three cells from each

The association pattern of the Ph1 chromosome

A total of 951 Ph1+ cells and 364 Ph1–cells from a female patient with chronic myelogenous leukemia was scored for acrocentric associations. The Ph1+ and Ph1-cells differed significantly in their association patterns. The average number of association groups per cell, the average size of the groups, and the total number of chromosomes involved in associations per cell were significantly lower in the Ph1+ cells. Although the Ph1 chromosome itself tended to be found in association more often than expected by chance, it appeared to associate at random with the other acrocentrics.