Immunodeficiency, Centromeric instability and Facial anomalies (ICF) syndrome is a group of rare autosomal recessive disorders. The immune disease in the ICF syndrome consists mainly of humoral immunodeficiency. T-cell dysfunction has previously been suspected to be part of the syndrome's spectrum. However, patients with ICF display, at a young age, a normal number of T cells that tend to decline throughout disease progression due to apoptosis. Biallelic mutations in the DNMT3B gene account for around 50% of ICF cases (ICF type 1). The remaining half may be linked to ZBTB24, CDCA7 or HELLS. Here we report a novel homozygous DNMT3B mutation (NM_ 006892; p.R826H) in a Lebanese family presenting in early infancy with severe combined immune deficiency (SCID). This work expands the clinical spectrum of the ICF syndrome and confirms the importance of tailoring therapeutic approaches for each patient with ICF syndrome, according to the clinical manifestations of his disease.

中文翻译：

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DNMT3B缺乏症表现为严重的联合免疫缺陷：病例报告。

免疫缺陷，着丝粒不稳定性和面部异常（ICF）综合征是一组罕见的常染色体隐性遗传疾病。ICF综合征中的免疫疾病主要包括体液免疫缺陷。T细胞功能障碍以前被怀疑是该综合征的一部分。但是，患有ICF的患者在年轻时会表现出正常数量的T细胞，由于细胞凋亡，在整个疾病进展过程中它们倾向于下降。DNMT3B基因中的双等位基因突变约占ICF病例（ICF 1型）的50％。其余的一半可以链接到ZBTB24，CDCA7或HELLS。在这里，我们报道了一个黎巴嫩人家庭中出现的新型纯合子DNMT3B突变（NM_ 006892； p.R826H），其婴儿早期出现严重的联合免疫缺陷症（SCID）。