Clinical and genetic epidemiology of Bardet-Biedl syndrome in Newfoundland: a 22-year prospective, population-based, cohort study.
Bardet-Biedl syndrome (BBS) and Laurence-Moon syndrome (LMS) have a similar phenotype, which includes retinal dystrophy, obesity, and hypogenitalism. They are differentiated by the presence of spasticity and the absence of polydactyly in LMS. The aims of this study were to describe the epidemiology of BBS and LMS, further define the phenotype, and examine genotype-phenotype correlation. The study involved 46 patients (26 males, 20 females) from 26 families, with a median age of 44 years (range 1-68 years). Assessments were performed in 1986, 1993, and 2001 and included neurological assessments, anthropometric measurements, and clinical photographs to assess dysmorphic features. The phenotype was highly variable within and between families. Impaired co-ordination and ataxia occurred in 86% (18/21). Thirty percent (14/46) met criteria for psychiatric illness; other medical problems included cholecystectomy in 37% (17/46) and asthma in 28% (13/46). Dysmorphic features included brachycephaly, large ears, and short, narrow palpebral fissures. There was no apparent correlation of clinical or dysmorphic features with genotype. Two patients were diagnosed clinically as LMS but both had mutations in a BBS gene. The features in this population do not support the notion that BBS and LMS are distinct. The lack of a genotype-phenotype correlation implies that BBS proteins interact and are necessary for the development of many organs.
Moore
Susan J
SJ
Clinical Epidemiology Unit, Memorial University, St John's, Newfoundland, Canada.
Green
Jane S
JS
Fan
Yanli
Y
Bhogal
Ashvinder K
AK
Dicks
Elizabeth
E
Fernandez
Bridget A
BA
Stefanelli
Mark
M
Murphy
Christopher
C
Cramer
Benvon C
BC
Dean
John C S
JC
Beales
Philip L
PL
Katsanis
Nicholas
N
Bassett
Anne S
AS
Davidson
William S
WS
Parfrey
Patrick S
PS
D000293:Adolescent; D000328:Adult; D000368:Aged; D020788:Bardet-Biedl Syndrome / Q000453:epidemiology / Q000235:genetics / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D005838:Genotype; D056385:Group II Chaperonins; D006801:Humans; D007223:Infant; D008297:Male; D008869:Microtubule-Associated Proteins; D008875:Middle Aged; D018832:Molecular Chaperones / Q000235:genetics; D009154:Mutation; D009523:Newfoundland and Labrador / Q000453:epidemiology; D010375:Pedigree; D010641:Phenotype; D015995:Prevalence; D011506:Proteins / Q000235:genetics; D013997:Time Factors
C464790:Bbs1 protein, human; C473309:Bbs2 protein, human; C414726:MKKS protein, human; D008869:Microtubule-Associated Proteins; D018832:Molecular Chaperones; D011506:Proteins; D056385:Group II Chaperonins