Percin E F, Percin S, Egilmez H, Sezgin I, Ozbas F, Akarsu A N
Department of Medical Biology and Genetics, Cumhuriyet University, Medical Faculty, Sivas, Turkey.
J Med Genet. 1998 Oct;35(10):868-74. doi: 10.1136/jmg.35.10.868.
Syndactyly type I is an autosomal dominant condition with complete or partial webbing between the third and fourth fingers or the second and third toes or both. We report here a previously undescribed phenotype of severe mesoaxial syndactyly and synostosis in patients born to affected parents. The characteristic features of these severe cases are (1) complete syndactyly and synostosis of the third and fourth fingers; (2) severe bone reduction in the proximal phalanges of the same fingers; (3) hypoplasia of the thumbs and halluces; (4) aplasia/hypoplasia of the middle phalanges of the second and fifth fingers; and (5) complete or partial soft tissue syndactyly of the toes. We report on three offspring with this phenotype from two different branches of a syndactyly type I family, suggesting that they may be homozygous for this condition. SSCP and linkage analysis indicated that neither HOXD13 nor other relevant genes in the chromosome 2q31 region was responsible for this phenotype.
I型并指（趾）症是一种常染色体显性疾病，表现为第三和第四手指之间、或第二和第三脚趾之间、或两者均出现完全或部分蹼状粘连。我们在此报告一种先前未被描述的严重中轴型并指（趾）症和骨性连接的表型，该表型出现在患病父母所生的子女中。这些严重病例的特征包括：（1）第三和第四手指完全并指（趾）且骨性连接；（2）同一手指近节指骨严重骨质减少；（3）拇指和拇趾发育不全；（4）第二和第五手指中节指骨发育不全/发育不良；（5）脚趾完全或部分软组织并指（趾）。我们报告了来自I型并指（趾）症家族两个不同分支的三名具有该表型的后代，提示他们可能是该病症的纯合子。单链构象多态性（SSCP）和连锁分析表明，HOXD13基因以及2q31染色体区域中的其他相关基因均与该表型无关。
