Alopecia-mental retardation syndrome (APMR) is a rare autosomal recessive neuro-dermal disorder. It is characterized by heterogeneous phenotypic features, that is, absence of hair on the scalp, eyelashes, and eyebrows and mild to severe intellectual disability. So far, approximately 14 families (i.e., Iranian, Pakistani, and Swiss) with APMR have been reported in the scientific literature. Its precise prevalence is still unknown, but according to a predictive estimate, it prevails with the ratio of 1 in 1,000,000 persons worldwide. Until now, only four loci (two characterized and two uncharacterized) have been reported to be involved in APMR. The pathogenic variants in alpha-2-HS-glycoprotein [AHSG; APMR1 (MIM#203650)] and lanosterol synthase [LSS; APMR4 (MIM#618840)] are the characterized genetic factors associated with APMR. Among them, AHSG was reported in a consanguineous Iranian family and LSS gene in a Swiss origin family, while the remaining two uncharacterized loci, that is, APMR2 and APMR3, are reported in the Pakistani population. The current mini-report discusses the molecular genetics and mutational spectrum of APMR syndrome, its differential diagnosis from related disorders, and prediction of plausible candidate genes in two uncharacterized loci.

中文翻译：

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脱发-精神发育迟滞综合征：一种罕见的神经-皮肤疾病的分子遗传学

脱发-精神发育迟滞综合征 (APMR) 是一种罕见的常染色体隐性神经-皮肤病。它的特征是异质的表型特征，即头皮、睫毛和眉毛上没有毛发，并且有轻度至重度的智力障碍。迄今为止，科学文献中已经报道了大约 14 个家庭（即伊朗人、巴基斯坦人和瑞士人）患有 APMR。它的确切流行率仍然未知，但根据预测估计，它在全世界以 1,000,000 人的比例盛行。到目前为止，仅报道了四个位点（两个已表征和两个未表征）与 APMR 相关。α-2-HS-糖蛋白 [ AHSG; APMR1 (MIM#203650)] 和羊毛甾醇合酶 [ LSS;APMR4 (MIM#618840)] 是与 APMR 相关的特征性遗传因素。其中，AHSG在一个伊朗血缘家族中被报道，LSS基因在一个瑞士血统中被报道，而其余​​两个未表征的基因座，即APMR2和APMR3，在巴基斯坦人群中报道。当前的小型报告讨论了 APMR 综合征的分子遗传学和突变谱、其与相关疾病的鉴别诊断以及对两个未表征基因座中可能的候选基因的预测。