摘要:

Presumptive monosomy for chromosome 21 was found in a male child with multiple malformations and severe psychomotor retardation. Chromosome analyses of cells from blood and skin samples were performed at intervals during the first few years of his life. In preparations stained with nonbanding as well as quinacrine, Giemsa, and reverse acridine orange banding techniques, only one No. 21 chromosome could be detected with no apparent abnormalities of the other chromosomes. The proband’s phenotypically normal father, paternal grandfather, brother, and paternal aunt have a deletion for a short segment of the long arm of a G-group chromosome. Genetic-marker studies allow the exclusion of a number of blood groups as being associated with No. 21. There is inconclusive evidence suggesting that expression of the Duffy blood group, which has been mapped to chromosome 1, may be influenced by genetic information on chromosome 21. This family is of potential value for further gene-mapping studie

ISSN:1424-8581    

DOI:10.1159/000130691

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

The chromosome banding patterns of the domestic rabbit, Oryctolagus cuniculus, the brush rabbit, Sylvilagus bachmani, and the snowshoe hare, Lepus americanus, are nearly identical except for minor differences in the amount of constitutive heterochromatin present. The major mechanisms of chromosome evolution in leporid lagomorphs are centric fusion and addition of heterochromatin. The G- and C-banding patterns of the pika, Ochotona princeps, revealed little easily recognized structural homology with the leporid species. Several tentative banding pattern matches were found for segments of some chromosomes of Ochotona, indicating that tandem fusions may have been responsible for structural modification of the early lagomorph genome. Chromosome evolution in the lagomorphs and the use of chromosomal data in studies of mammalian systematics are discussed.

ISSN:1424-8581    

DOI:10.1159/000130692

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

A stable human-Chinese hamster ovary cell hybrid has been produced which, in addition to the complement of Chinese hamster ovary (CHO-K1) chromosomes, contains only one human chromosome, No. 11. The human cell-surface antigens whose expression is controlled by human chromosome 11, and are expressed by this hybrid, have been defined as the AL immunogenetic complex. Although one component of this immunogenetic complex (a1) is also expressed by human red blood cells, a second component (a2) is not. Killing of an aι+ hybrid by anti-a1 serum and complement can be completely inhibited by glycophorin, the major glycoprotein component of the human erythrocyte membrane. In the presence of complement, antiserum prepared against glycophorin will kill only those cells which express a1. The anti-a1 killing activity of the anti-glycophorin can be adsorbed out only by those cells which express ai. Therefore, it is concluded that the ai cell-surface antigen has at least one antigenic component in common with glycophorin

ISSN:1424-8581    

DOI:10.1159/000130693

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

Meiotic studies have been carried out in five human male translocation heterozygotes. An account of the cytological observations is given together with information concerning their reproductive history and fertility.

ISSN:1424-8581    

DOI:10.1159/000130694

出版商:S. Karger AG    

年代:1976

数据来源: Karger

ISSN:1424-8581    

DOI:10.1159/000130695

出版商:S. Karger AG    

年代:1976

数据来源: Karger