Syndactyly type II (synpolydactyly (SPD)) is an autosomal dominant condition with typical abnormalities of the distal parts of both upper and lower limbs. We report here a previously undescribed phenotypic feature of people with severe hand and foot deformities who were born to two affected parents. This is the first example of SPD subjects manifesting a very distinctive phenotype, suggesting t...

The mouse mutant Doublefoot (Dbf) shows preaxial polydactyly of all four limbs. We have analysed limb development in this mutant with respect to morphogenesis, gene expression patterns and ectopic polarising activity. The results reveal a gain-of-function mutation at a locus that mediates pattern formation in the developing limb. Shh expression is identical with that of wild-type embryos, i.e. ...

Cowden syndrome (CS), also known as multiple hamartoma-neoplasia syndrome, is an autosomal dominant disease with numerous possible clinical manifestations. Commonly present are skin changes including acral keratoses and facial trichilemmomas, as well as oral papillomas and scrotal tongue. There is an increased risk of malignancies including breast, thyroid, and endometrial cancers. Hamartomas m...

  Radial polydactyly, the most common digital duplication in Asian and white populations, has a wide range of manifestations. Its classification is useful for planning and assessing surgical treatment. Our patient had four thumbs, duplicated radial carpal bones, and a bifurcated radius. This presentation is not covered by any of the current classifications. To the best of our knowledge, this is...

BACKGROUND Polydactyly is the most common congenital hand deformity. There is currently no consensus among pediatricians or hand surgeons regarding optimal management of ulnar (post-axial) type B polydactyly leading to uncertainty in initial treatment decisions for infants with this type of deformity. METHODS Parents of newborns with type B ulnar polydactyly were enrolled in a prospective, no...

Members of the Abdominal-B-related Hox gene subfamily (belonging to homology groups 9 to 13) are coordinately expressed during limb bud development. Only two genes from homology group 13 (Hoxa-13 and Hoxd-13) are specifically expressed in the developing distal region (the autopod), which displays the most complex and evolutionarily flexible pattern among limb 'segments'. We report here that tar...

Several 5' members of the Hoxd cluster are expressed in nested posterior-distal domains of the limb bud suggesting a role in regulating anteroposterior pattern of skeletal elements. While loss-of-function mutants have demonstrated a regulatory role for these genes in the developing limb, extensive functional overlaps between various different Hox genes has hampered elucidation of the roles play...