A simplified method of demonstrating Giemsa-band pattern in human chromosomes

Eukaryotic genome: model considerations

The paper presents a new model of chromosome structure based on the assumption that multiple circular subunits of DNA exist. The essential difference with previously described models is the circular DNA unit forms a central chromosome axis. Chromosome configurations during various phases of the cell cycle depend on the various conformations of this central integrating unit. The described model can be generalized for all haploid set of eukaryotic nucleus. Some aspects of the chromosome structure and their functions have been discussed.

Partial Turner's syndrome in four girls with Xq duplication and Xp deficiency

Four girls with some clinical symptoms of Turner's syndrome had Xq duplication and Xp deficiency, their karyotypes being 46,X,dup(X)(p113;q11), 46,X,dup(X)(p212;q211), 46,X,dup(X)(p225;q13), and 46,X,dup(X)(p222;q213). No mosaicism was found. The major clinical findings, short stature, lack of pterygium colli, and no continuous gamete production, are compared with those in three previously published cases.

Chromosomes in the Cornelia de Lange syndrome

This paper summarizes previous chromosomal studies in patients with the Cornelia de Lange syndrome showing abnormal karyotypes. We report on 45 cases of the Cornelia de Lange syndrome clinically examined by one of us (B.B.) and chromosomally studied using several different methods. Two abnormal karyotypes were found: a girl with a 45,X karyotype and a boy with a (13q14q) translocation which was also found in his phenotypically normal mother and maternal grandmother. Because of recent reports of the duplication 3q syndrome and Cornelia de Lange-like phenotypes, prometaphase chromosomes were studied in 31 patients. All karyotypes were normal. As there was an excess of boys among the younger patients, special examination for the fragile site on X(q28) was carried out. This abnormality was not found. Even though no patients with the dup(3q) syndrome were found among the Cornelia de Lange patients, chromosome studies are recommended especially in connection with genetic counselling. A recurrence rate of 2-5% must still be considered for the Cornelia de Lange syndrome.