Premium
The segmentary structure of the human X‐chromosome compared with that of rodents
Author(s) -
Oguma Kan
Publication year - 1937
Publication title -
journal of morphology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.652
H-Index - 74
eISSN - 1097-4687
pISSN - 0362-2525
DOI - 10.1002/jmor.1050610105
Subject(s) - biology , chromosome , spermatocyte , x chromosome , fixation (population genetics) , genetics , karyotype , y chromosome , evolutionary biology , anatomy , meiosis , gene
Testicular cells obtained from Manchurians were chiefly employed for the study. In the primary spermatocyte the X‐chromosome presents a three‐segmented structure similar to that of rats. This was not clear in our previous studies, probably due to some technical failure. Of the three segments, one frequently assumes a shape suggestive of the Y‐chromosome to some authors, but this never disjoins in the first maturation division, and accordingly it cannot be regarded as a true Y. The three segments are designated as P, D 1 and D 2 segment, the latter two are occasionally combined to form a single D segment. The P segment presents such a great modification of shape, that it led some authors to misinterpretation. The identification of the X‐chromosome was uncertain in the spermatogonial group of chromosomes, but in every case of good fixation forty‐seven distinct chromosomes were found.