Author/Authors :
Rajangam، Sayee نويسنده , , Tilak، Preetha نويسنده , , N، Aruna نويسنده Division of Human Genetics, Department Of Anatomy, St. Johns Medical College, Bangalore, India , , Devi، Rema نويسنده ,
Abstract :
Background: Division of Human Genetics (DHG) is a referral center for karyotyping and
counseling to the couples as well as to the individuals referred with bad obstetric history and
infertility.
Materials and Methods: From 1972 to 2003, overall 1666 couples and 131 female partners
with bad obstetric history (BOH) such as; spontaneous abortions, live births with congenital
malformations and still born and 73 infertile male partners have been referred for
chromosomal analysis.
Results: The chromosomal abnormality was found in 4.4% (83) of the sample studied.
Chromosomal abnormality was seen in 56 couples (3.4%), 15 female (11.5%) and 12 male
(16.4%) partners. The numerical chromosomal abnormality were seen in 34 (41%) and the
structural abnormalities in 49 (59%) cases. The numerical chromosomal abnormalities were
associated with sex chromosomes as follows (the number of cases are shown in parenthesis):
47, XXY (9); 46, XY/ 47, XXY (2); 46, XY/ 48, XXXY (1); 46, XY/ 47, XYY (2) and X
mosaicism; 45, X/ 46, XX (14); 46, XX/ 47, XXX (6). The structural anomalies were 40
translocations and 9 duplication/ deletion/ marker/ iso chromosome for the X chromosome;
Male: 46,XY/ 47,XY+ mar (1); Female: 45,X/ 47,XX+mar (1); 46,XX/ 47,XX+mar (1);
47,XX+frag (1); 46,X,Xq- (2); 46,X,Xp- (1); 46,X,Xp+ (1); 45,X/46,X,i(Xq)(1). The
frequently involved chromosomes in the translocations were 4, 11, 15 and X. There were
three X; autosomal translocations and a unique combination of translocation 1; 15 in the
parents of a female carrier and 13; 14 in a non- consanguineous couple. On the whole, 57.5%
of the females (23/ 40) were translocation carriers. Non-significant chromosome
polymorphisms were observed in 79 cases (4.2%).
Conclusion: The current study has demonstrated the presence of the chromosomal
abnormality and its influence in reproductive failure. On an average, in this study one in 56
couple and one in 12 males with infertility or one in 15 females with BOH has had a
chromosomal abnormality as the genetic cause. The identification of chromosomal
abnormality as the etiology has facilitated the counseling and appropriate management.