These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: An autosomal dominant triphalangeal thumb: polysyndactyly syndrome with variable expression in a large Indian family maps to 7q36.
    Author: Radhakrishna U, Blouin JL, Solanki JV, Dhoriani GM, Antonarakis SE.
    Journal: Am J Med Genet; 1996 Dec 11; 66(2):209-15. PubMed ID: 8958333.
    Abstract:
    Hereditary developmental abnormalities of the upper or lower limbs in humans are easily recognizable phenotypes that can be used in the mapping and cloning of genes involved in normal human development. We studied a large Indian pedigree (UR002) with an autosomal dominant triphalangeal thumb (TPT) and polysyndactyly (PSD). The abnormalities were present only in the upper limbs, and the phenotype was fully penetrant. The expression of the phenotype was variable and ranged from unilateral TPT to bilateral TPT, preaxial du-, tri-, or quadruplication of the thumb, or syndactyly of multiple thumbs. There were 112 affected individuals in the pedigree. Previous linkage analyses on apparently similar phenotypes have identified a locus at 7q36 [Heutink et al., 1994, Nature Genet 6:287-291; Tsukurov et al., 1994]. To map the gene responsible for the TPT-PSD in family UR002, we performed linkage analysis in DNA from 47 affected and 7 normal individuals. Marker D7S550, located at 7q36, yielded a maximum LOD score of 11.31 at theta = 0.00. Additional markers in the region also showed no recombination. These data indicate that the gene responsible for the hand abnormality in pedigree UR002 maps to the same region as that in previous pedigrees with similar phenotype. Further analyses of recombinants among all the linked families by using new polymorphic markers will narrow the critical genomic region and facilitate positional cloning of the elusive gene.
    [Abstract] [Full Text] [Related] [New Search]