THE PROFILE OF MAJOR CONGENITAL-ABNORMALITIES IN THE UNITED-ARAB-EMIRATES (UAE) POPULATION

The aim of this study was to establish the profile of major congenital malformations in the United Arab Emirates (UAE) population which has a high rate of consanguinity. All births with birth weight above 500 g in the three hospitals in the A1 Ain Medical District of UAE were pro spectively studied from January 1992 to January 1994. About 98% of the births in the district occur in these three hospitals. Detailed famil y history and clinical and relevant laboratory investigations were rec orded in each case. Necropsy was not permitted. The major malformation s were classified as multiple or isolated single system abnormalities as well as genetic or non-genetic disorders. Of the 16 419 births whic h occurred during the two year period, 173 (10.5/1000 births) had majo r malformations, 90 (52%) had multiple malformations, and 83 (47.97%) had involvement of a single system. Of the infants with multiple malfo rmations, 43 had recognised syndromes, most of which are autosomal rec essive disorders with a high frequency of rare syndromes. Twenty eight (31%) had chromosomal abnormalities. The most common systems involved in infants with isolated single system malformations include gastroin testinal (33), central nervous system (17), and cardiovascular (10). W hile the consanguinity rate was similar (57% v 54%), the frequency of first cousin marriages was much higher (51% v 30%) in the study group compared with the figures for the general population. The consanguinit y rate was highest among the syndrome eases, and related parents were more likely to have infants with multiple malformations than an isolat ed single system abnormality with a relative risk of 1.69 (95% CL 1.27 -2.24). Genetic factors could be implicated in 116 (67%) of the 173 ca ses of major malformations and 49 (28%) were potentially preventable. The study suggests that genetic disorders account for a significant pr oportion of congenital malformations in the UAE and, thus, a genetic s ervice should be provided as part of the preventive care programme.