Osman DEMİRHAN, Deniz TAŞTEMİR, Nejat NARLI, Kenan ÖZCAN, Süreyya SOYUPAK

Chromosome and p63 gene analysis of an ınfant with ectrodactyly–split hand and foot malformation

Amaç: Yarık el- yarık ayak kusurlu oluşumu (SHFM), parmak oluşum merkezindeki duraksama sonucunda meydana gelir ve el ile ayaklarda medyan yarıklar, sindaktili ve diğer fenotipik anomaliler ile genellikle ilişkili bulunan falanj, metakarpus ve metatarsuslardaki aplazi veya hipoplazi olarak kendini göstermektedir. Bu çalışmada SHFM'li bir çocukta SHFM'in genetik mekanizmasının araştırılması amaçlandı. Materyal ve metot: Bu çalışmada, baş ve işaret parmağı arasında sindaktilisi olan yarık el ile sindaktilişi olan düz taban ayağa sahip olan 10 günlük bir erkek çocukta sitogenetik ve moleküler genetik analizler uygulandı. Bulgular: Hastamızda, 4ql2'de kırılma, 9ql 1-13 band bölgesin'de frajilite ve 9qh+ gibi çeşitli kromozomal yeniden düzenlenmeler saptandı. Sitogenetik bulgular literatür bulguları ile benzerlik gösterirken, p63'deki moleküler analiz ise herhangi bir mutasyonun olmadığını gösterdi. Sonuç: Hastamızın fenotipi muhtemelen, p63 geninin değişken ekspresivitesi ve penetransı nedeniyle ve diğer genetik faktörler veya SHFM genindeki diğer dört bölgede lokalize olan mutasyonlar nedeniyle oluşmuş olabilir. Non-sendromik yarık damağa yatkınlık oluşturan diğer minor modifiye edici genler de EEC sendromunun yarık damak oluşumuna katkıda bulunabilir.

Ektrodaktili-Yarık el ve ayak malformasyonlu bir olgunun kromozom ve p63 gen mutasyon analizleri

Aim: Split hand-split foot malformation (SHFM) results from central ray reduction and presents as median clefts of the hands and feet, syndactyly, aplasia or hypoplasia of the phalanges, metacarpals and metatarsals, which are frequently associated with other phenotypic abnormalities. We aimed to investigate the genetic pathway of SHFM in a child. Materials and methods: Cytogenetic and molecular genetic analysis was performed in a 10-day-old boy with split-syndactyly hand and flat-syndactyly foot. Results: We found a complex chromosomal rearrangement including breaks in 4ql2, fragility in the 9ql 1-13 band region and 9qh+. Cytogenetic results agree with the literature findings. The mutation analysis of the p63 gene revealed no mutation. Conclusion: The phenotype of our patient may be due to variable expressivity and penetrance of the p63 gene and to other genetic factors, or the mutation can be located in the other 4 loci for SHFM. Additional minor modifying genes, which predispose to non-syndromic cleft palate, could also contribute to the expression of the cleft palate component of the EEC syndrome.

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