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

Search MEDLINE/PubMed


  • Title: Spontaneous and inheritable R555Q mutation in the TGFBI/BIGH3 gene in two unrelated families exhibiting Bowman's layer corneal dystrophy.
    Author: Zhao XC, Nakamura H, Subramanyam S, Stock LE, Gillette TE, Yoshikawa S, Ma X, Yee RW.
    Journal: Ophthalmology; 2007 Nov; 114(11):e39-46. PubMed ID: 17980739.
    Abstract:
    PURPOSE: Bowman's layer corneal dystrophies (CDBs) include 2 distinct types: CDB1, or Reis-Bücklers (RBCD), and CDB2, or Thiel-Behnke (TBCD). We studied the genetic basis of 2 cases of apparent spontaneous CDB mutations and attempted to determine if these are sporadic and inheritable mutations. DESIGN: Retrospective molecular genetic study and case report. PARTICIPANTS: Twelve patients were recruited from 2 unrelated families for this study, including 2 affected individuals from one family (family A) and 1 affected individual from another (family B). METHODS: Slit-lamp examination was performed for each patient to determine the disease phenotype. Histological analysis of affected cornea specimens was used for identification of pathogenic corneal opacities in 2 affected patients from family A. MAIN OUTCOME MEASURES: Genomic DNA was isolated from the blood samples and used for mutation screening of the TGFBI/BIGH3 gene. Sixteen polymorphic DNA markers from 9 different chromosomes were used to establish the maternity and paternity of the 2 probands. RESULTS: The 2 families were confirmed to be unrelated. The age onset of ocular symptoms was <2 years for all 3 affected patients. Clinical diagnoses of CDB1 (RBCD) and CDB2 (TBCD) were made for probands A and B, respectively. The affected corneas showed epithelial haze with diffuse, irregular, patchy opacities in a honeycomb and geographic pattern. Subepithelial plaques, increased trichome staining of anterior stroma, and irregular Bowman's layer were observed. An R555Q mutation was found in TGFBI/BIGH3 in the 2 probands but not in their parents. The son of proband A was also affected and apparently inherited his disease allele from his father. CONCLUSION: The R555Q mutation occurred spontaneously and independently in the 2 unrelated CDB families and was confirmed to be transmitted to the next generation in 1 of the 2 families. These findings strongly support the notion that a genetic diagnosis should be determined for CDB and other dystrophies associated with mutations in TGFBI/BIGH3. The discovery of a spontaneous mutation should alert clinicians to be aware of the existence of genetic alterations for their patients without apparent family history of the disease.
    [Abstract] [Full Text] [Related] [New Search]