Defective Levothyroxine Response in a Patient with Dyshormonogenic Congenital Hypothyroidism Caused by a Concurrent Pathogenic Variant in Thyroid Hormone Receptor-β.

Pituitary resistance to thyroid hormone (PRTH) is often seen in congenital hypothyroidism (CH), presenting as elevated thyrotropin (TSH) values despite (high-)normal thyroid hormone (TH) values achieved by levothyroxine treatment. In this study, we describe a girl with CH who was referred because of difficulties interpreting thyroid function tests. She was thought to have PRTH associated with CH, but genetic studies discovered a pathogenic variant in , causing resistance to TH (RTH-β).

Johanson-Blizzard syndrome caused by identical UBR1 mutations in two unrelated girls, one with a cardiomyopathy.

We report on two apparently unrelated girls with Johanson-Blizzard syndrome (JBS), in both children caused by a homozygous IVS26+5G>A mutation in the UBR1 gene. In both cases the parents are consanguineous and more sibs are affected. The somewhat mild phenotype (with no or slight mental retardation) in these two JBS families might be explained by residual UBR1 activity.

Human alpha-N-acetylgalactosaminidase (alpha-NAGA) deficiency: no association with neuroaxonal dystrophy?

Two new individuals with alpha-NAGA deficiency are presented. The index patient, 3 years old, has congenital cataract, slight motor retardation and secondary demyelinisation. Screening of his sibs revealed an alpha-NAGA deficiency in his 7-year-old healthy brother who had no clinical or neurological symptoms.