New insights into X‐linked adrenal hypoplasia congenita from a novel splice‐site variant of NR0B1 and adrenal CT images

Abstract

Background X‐linked adrenal hypoplasia congenita (AHC) is a rare disorder, often manifesting as primary adrenal insufficiency (PAI) and hypogonadotropic hypogonadism (HH), and caused by variants of NR0B1, most of which are frame‐shifting variants, and few splice‐site variants. Methods and Results Here, a novel splice‐site variant of NR0B1 (NM_000475.4), c.1169‐2A>T (patient 1), and a stop‐loss variant of NR0B1 c.1411T>C (patient 2) are described in this study. We perform minigene assays for the splice‐site variant (c.1169‐2A>T) and determine that the variant causes exon 2 skipping. Moreover, the defect of NR0B1 protein may bring about the severe phenotype of the patient. Through 8 years of follow‐up, we compare the CT images from 8 years ago with the latest image, and observe the CT image change of adrenal in patient 2 (from the increased thickness of adrenal to adrenal atrophy). Conclusion X‐linked adrenal hypoplasia congenita is produced by variants of NR0B1. We report a case that presents a novel splice‐site variant, which has been verified that it could lead to the exon 2 skipping in the RNA splicing progress. Moreover, we report the adrenal CT image change of patient 2, which has never been referred to before, and expand the spectrum of X‐linked AHC characteristics.