No mutations were detected in any of the candidate genes. In situ thyroid gland represented 71.1% of all cases of permanent primary congenital hypothyroidism, followed by hypoplasia (9.6%), ectopia (78%), hemiagenesis (6.0%) and agenesis (5.5%). The highest neonatal screening TSH levels were in the agenesis group (p < 0.001).
Conclusions:
Thyroid dysgenesis is possibly a polygenic disorder and epigenetic factors could to be implicated in these pathogeneses.