Genetics: Mosaic in X & Y

“There’s nothing like a dame,” sang the Navymen in South Pacific. Not so, say physiologists. There are people who are something like a dame but are really men, or even a combination of male and female because nature has scrambled their chromosomes. Last week a star Polish athlete found “herself” in one of these anomalous categories and was barred on medical grounds from international competition.

Ewa Klobukowska, 21, born in Warsaw, was raised as a girl and always thought of herself as a girl. She grew to a lithe and powerful 5 ft. 7 in. Though she had negligible bust development she seemed, with shoulder-length blonde hair, sufficiently feminine to attract plenty of male dancing partners in Warsaw night spots. When she cropped her hair recently she looked a bit less feminine, but after the International Amateur Athletic Federation ordered sex tests for female athletes, she paraded naked before three women doctors last year in Budapest and was passed as a woman without question.

Irked by complaints that previous nets had not screened out all contestants of doubtful femaleness, the I.A.A.F. ordered chromosome tests for European Cup competitors at Kiev. Ewa, co-holder of the women’s 100-meter world record (11.1 sec.), saw no need to duck the test and readily submitted to having a few cells scraped from inside her cheek for chromosome analysis. On the basis of the microscope’s evidence, three Russian and three Hungarian doctors gave the fatal verdict: Ewa is not a woman because she has “one chromo some too many.”

Which chromosome, they did not say. A normal woman has 22 pairs of nonsex chromosomes, like a man, plus two x chromosomes to determine femaleness. A normal man has one x, but his y chromosome is decisive and establishes maleness. A fairly common case of “one chromosome too many” is an xxy combination, but this is accompanied by external male genitalia and poor, nonathletic physical development. More probably, Ewa is a mosaic, with some xyy cells, and others containing a single x and nothing else.