Luo et al. 1 reported two cases of autosomal dominant pseudohypoparathyroidism type 1B (AD-PHP1B) and reviewed literature about the genetic and epigenetic characteristics of AD-PHP1B. Pseudohypoparathyroidism (PHP) is a cluster of heterogeneous diseases characterized by hypocalcemia and hyperphosphatemia due to resistance to parathyroid hormone (PTH). PHP1B almost results from methylation abnormalities of the maternal differentially methylated regions (DMRs) and can be divided into sporadic PHP1B and AD-PHP1B 1. As mentioned in this article 1, AD-PHP1B is caused by heterozygous maternal deletions within GNAS or STX16, which are associated with loss of methylation at the A/B DMR alone or at all maternally methylated GNAS exons. While sporadic PHP1B remains unclear at the molecular level, except for approximately 10% of the patients caused by paternal uniparental isodisomy or heterodisomy involving chromosome 20q (patUPD20q) 2. Here, we would like to present a rare case of sporadic PHP1B occurring in association with hypokalemia.

中文翻译：

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伴有低钾血症的散发性1B型假性甲状旁腺功能减退症一例


罗等人。 1报告了两例常染色体显性假性甲状旁腺功能减退症1B型（AD-PHP1B），并回顾了有关AD-PHP1B遗传和表观遗传特征的文献。假性甲状旁腺功能减退症（PHP）是一组因甲状旁腺激素（PTH）抵抗而导致的以低钙血症和高磷血症为特征的异质性疾病。 PHP1B 几乎是由母体差异甲基化区域（DMR）的甲基化异常引起的，可分为散发性 PHP1B 和 AD-PHP1B 1。正如本文 1 中提到的，AD-PHP1B 是由 GNAS 或 STX16 内的杂合子母体缺失引起的，与单独的 A/B DMR 或所有母源甲基化 GNAS 外显子的甲基化缺失相关。虽然散发性 PHP1B 在分子水平上仍不清楚，但大约 10% 的患者是由涉及染色体 20q (patUPD20q)2 的父亲单亲同二体或异二体引起的。在此，我们想介绍一例与以下疾病相关的散发性 PHP1B 罕见病例：低钾血症。