Occurrence of cardiac malformations in relatives of children with transposition of the great arteries.
Transposition of the great arteries (TGA) is the most common cyanotic cardiac malformation, representing 5-7% of all cardiac malformations. Previous estimates of the frequency of cardiac malformations in sibs of probands range from 0-1.7%. This study ascertained the frequency of congenital cardiac malformations in relatives of 271 probands with TGA, who were grouped according to the type of TGA present. These include dextro (d-TGA), levo (l-TGA), complex TGA, and asplenia with TGA. In the d-TGA cases there were 369 sibs, one of whom had a cardiac malformation (0.27%). There were 50 sibs in the l-TGA group, with one sib having a cardiac malformation (2.00%). Cardiac malformations were found in 2 of 143 (1.40%) sibs of the complex TGA index cases, and 1 of 50 (2.00%) sibs in the asplenia with TGA group. The overall recurrence risk of cardiac malformations in sibs of TGA probands was 0.82%. Cardiac malformations in parents of probands were found in 0.29% of d-TGA, 0% of l-TGA, 1.54% of complex TGA, and 0% of asplenia with TGA, giving an overall parental occurrence of 0.55%. This is the first study to provide information on the different types of TGA in evaluating sib occurrence. It provides necessary genetic counseling information for families of probands with TGA.
Becker
T A
TA
Ray & Hattie Anderson Center, Department of Pediatrics, University of Minnesota, Minneapolis, USA.
Van Amber
R
R
Moller
J H
JH
Pierpont
M E
ME
D000328:Adult; D005190:Family; D005260:Female; D005817:Genetic Counseling; D006330:Heart Defects, Congenital / Q000453:epidemiology / Q000235:genetics*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D012307:Risk Factors; D014188:Transposition of Great Vessels / Q000235:genetics*