BACKGROUND: The scant data on ethnic differences in the prevalence of congenital hypothyroidism (CH) have generally not taken etiology of CH into account. Our hypothesis is that the prevalence of CH due to thyroid dysgenesis (TD) varies by ethnicity. METHODS: This case-control study included all patients with CH due to TD (a condition of unknown origin) or to dyshormonogenesis (DH, of known autosomal recessive transmission) between 1987 and 2009. Etiology was established by (99m)Tc scintigraphy. The parents self-assessed their ethnicity, which we grouped in Caucasian, Hispanic, black, Asian, and Maghreb/Middle East. We compared ethnicity between the 190 patients with TD (147 ectopies, 40 athyreoses, and 3 orthotopic hypoplasias) and the 44 patients with DH. Ethnicity was also compared to the reference population of the city of Montreal. Prevalence odds ratios (POR) were calculated and compared by the bilateral Fisher's exact test. RESULTS: The ethnic composition of the DH group was similar to that of the reference population. In blacks, TD prevalence of 1 in 190 (0.5%) was low compared to that of DH (4 in 44; 9.1%; POR 0.06; 95% confidence interval: 0.001-0.56; p = 0.005). In contrast, Caucasians showed an increased TD prevalence of 166 in 190 (87.3%) compared to that of DH (30 in 44; 68.2%; POR 3.21; 95% confidence interval: 1.37-7.34; p = 0.0052). No statistically significant differences were observed between other ethnic groups. CONCLUSION: TD is less prevalent in blacks and more prevalent in Caucasians. Blacks being more genetically diverse, this is an argument for an oligogenic inheritance of susceptibility to TD.
BACKGROUND: The scant data on ethnic differences in the prevalence of congenital hypothyroidism (CH) have generally not taken etiology of CH into account. Our hypothesis is that the prevalence of CH due to thyroid dysgenesis (TD) varies by ethnicity. METHODS: This case-control study included all patients with CH due to TD (a condition of unknown origin) or to dyshormonogenesis (DH, of known autosomal recessive transmission) between 1987 and 2009. Etiology was established by (99m)Tc scintigraphy. The parents self-assessed their ethnicity, which we grouped in Caucasian, Hispanic, black, Asian, and Maghreb/Middle East. We compared ethnicity between the 190 patients with TD (147 ectopies, 40 athyreoses, and 3 orthotopic hypoplasias) and the 44 patients with DH. Ethnicity was also compared to the reference population of the city of Montreal. Prevalence odds ratios (POR) were calculated and compared by the bilateral Fisher's exact test. RESULTS: The ethnic composition of the DH group was similar to that of the reference population. In blacks, TD prevalence of 1 in 190 (0.5%) was low compared to that of DH (4 in 44; 9.1%; POR 0.06; 95% confidence interval: 0.001-0.56; p = 0.005). In contrast, Caucasians showed an increased TD prevalence of 166 in 190 (87.3%) compared to that of DH (30 in 44; 68.2%; POR 3.21; 95% confidence interval: 1.37-7.34; p = 0.0052). No statistically significant differences were observed between other ethnic groups. CONCLUSION: TD is less prevalent in blacks and more prevalent in Caucasians. Blacks being more genetically diverse, this is an argument for an oligogenic inheritance of susceptibility to TD.
Authors: Elena Amendola; Pasquale De Luca; Paolo Emidio Macchia; Daniela Terracciano; Annamaria Rosica; Gennaro Chiappetta; Shioko Kimura; Ahmed Mansouri; Andrea Affuso; Claudio Arra; Vincenzo Macchia; Roberto Di Lauro; Mario De Felice Journal: Endocrinology Date: 2005-09-08 Impact factor: 4.736
Authors: Amanda H Mortensen; Qing Fang; Michelle T Fleming; Thomas J Jones; Alexandre Z Daly; Kenneth R Johnson; Sally A Camper Journal: Mamm Genome Date: 2019-02-18 Impact factor: 2.957
Authors: Richard J Q McNally; Jeremy H Jones; Mohamad Guftar Shaikh; Malcolm D C Donaldson; Karen Blakey; Tim D Cheetham Journal: Thyroid Date: 2020-12-29 Impact factor: 6.568