Bijlsma E K, Aalfs C M, Sluitjer S, Oude Luttikhuis M E, Trembath R C, Hoovers J M, Hennekam R C
Department of Clinical Genetics, Academic Medical Centre, University of Amsterdam, The Netherlands.
J Med Genet. 1999 Aug;36(8):604-9.
Recently five patients with an Albright hereditary osteodystrophy (AHO)-like phenotype were reported to have a subtelomeric deletion of the long arm of chromosome 2. These patients showed a striking resemblance to a number of patients from a large pedigree known to us for a long time. After molecular confirmation of a subtelomeric deletion in one patient, FISH analysis was used and a cryptic translocation between the long arms of chromosomes 2 and 8, t(2;8)(q37.3;q24.3), was detected. Remarkably, five proven and 10 probable cases with a 2qter deletion were found in the family, but none with an 8qter deletion. This was not explained by increased fetal loss. The major clinical characteristics of terminal 2q deletion are a short, stocky build, round face, sparse hair, deeply set eyes, bulbous nose, thin vermilion border, brachymetaphalangism, seizures, and developmental delay. A specific behavioural phenotype consisting of periods of hyperkinesia and aggression can develop with age. The overall phenotype is sufficiently characteristic to allow clinical recognition. The cytogenetic and molecular studies did not narrow down the common deleted region. Both testing of additional 2q markers and characterisation of other AHO-like patients with 2q37 microdeletions may help to define the candidate gene region.
最近有报道称，5例具有类奥尔布赖特遗传性骨营养不良（AHO）表型的患者存在2号染色体长臂的亚端粒缺失。这些患者与我们长期以来所熟知的一个大家系中的许多患者表现出惊人的相似之处。在对1例患者的亚端粒缺失进行分子确认后，采用荧光原位杂交（FISH）分析，检测到2号和8号染色体长臂之间存在隐匿性易位，即t(2;8)(q37.3;q24.3)。值得注意的是，在该家族中发现了5例经证实和10例可能的2q末端缺失病例，但无一例8q末端缺失病例。这无法用胎儿丢失增加来解释。2q末端缺失的主要临床特征包括身材矮小、矮胖、圆脸、头发稀疏、眼窝深陷、蒜头鼻、唇红缘薄、短指（趾）畸形、癫痫发作和发育迟缓。随着年龄增长，可能会出现由运动亢进和攻击行为期组成的特定行为表型。总体表型具有足够的特征性，可实现临床识别。细胞遗传学和分子研究并未缩小共同缺失区域。检测更多的2q标记以及对其他具有2q37微缺失的类AHO患者进行特征分析，可能有助于确定候选基因区域。
