Genomewide linkage scans for ocular refraction and meta-analysis of four populations in the Myopia Family Study.

Purpose: Genomewide linkage scans were performed in Caucasian (CAUC) and Old Order Amish (OOA) families to identify genomic regions containing genes responsible for refractive error control. We also performed a meta-analysis by combining these results with our previous linkage results from Ashkenazi Jewish (ASHK) and African American (AFRAM) families.

Methods: Two hundred seventy-one CAUC and 411 OOA participants (36 and 61 families, respectively) were recruited to participate in the Myopia Family Study.

Genome-wide scan of African-American and white families for linkage to myopia.

Purpose: To identify myopia susceptibility genes influencing common myopia in 94 African-American and 36 White families.

Design: A prospective study of families with myopia consisting of a minimum of two individuals affected with myopia.

Methods: Extended families consisting of at least two siblings affected with myopia were ascertained.

Establishing an adjusted p-value threshold to control the family-wide type 1 error in genome wide association studies.

Background: By assaying hundreds of thousands of single nucleotide polymorphisms, genome wide association studies (GWAS) allow for a powerful, unbiased review of the entire genome to localize common genetic variants that influence health and disease. Although it is widely recognized that some correction for multiple testing is necessary, in order to control the family-wide Type 1 Error in genetic association studies, it is not clear which method to utilize. One simple approach is to perform a Bonferroni correction using all n single nucleotide polymorphisms (SNPs) across the genome; however this approach is highly conservative and would "overcorrect" for SNPs that are not truly independent.

Genome-wide scan of additional Jewish families confirms linkage of a myopia susceptibility locus to chromosome 22q12.

Purpose: A genome-wide scan was previously reported for myopia in Ashkenazi Jews. In order to confirm the previous linkage peaks, a collection of DNA samples from 19 new Ashkenazi Jewish families were tested for linkage in a genome wide scan.

Methods: Families were ascertained from an Orthodox Ashkenazi Jewish community through mailings.

Genome-wide scan for myopia in the Old Order Amish.

Purpose: To identify myopia susceptibility genes influencing common myopia in 34 Old Order Amish families, a genetically well-defined founder population.

Design: A prospective study of families with myopia consisting of a minimum of two individuals affected with myopia.

Methods: Extended families consisting of at least two siblings affected with myopia were ascertained.

Candidate high myopia loci on chromosomes 18p and 12q do not play a major role in susceptibility to common myopia.

Background: To determine whether previously reported loci predisposing to nonsyndromic high myopia show linkage to common myopia in pedigrees from two ethnic groups: Ashkenazi Jewish and Amish. We hypothesized that these high myopia loci might exhibit allelic heterogeneity and be responsible for moderate /mild or common myopia.

Methods: Cycloplegic and manifest refraction were performed on 38 Jewish and 40 Amish families.

Genomewide linkage scan for myopia susceptibility loci among Ashkenazi Jewish families shows evidence of linkage on chromosome 22q12.

Mild/moderate (common) myopia is a very common disorder, with both genetic and environmental influences. The environmental factors are related to near work and can be measured. There are no known genetic loci for common myopia.

A genome-wide scan for loci predisposing to non-syndromic cleft lip with or without cleft palate in two large Syrian families.

Non-syndromic cleft lip with/without cleft palate (CL/P) is a common, usually non-fatal birth defect of complex etiology. Several segregation analyses have demonstrated that genetic factors are important in the pathogenesis of CL/P, most likely through the interaction of several genes of modest effects. The aim of this study was to perform a genome-wide linkage analysis to identify/search for candidate gene loci for CL/P.