A missense mutation in PIK3R5 gene in a family with ataxia and oculomotor apraxia.

Autosomal recessive ataxias are heterogeneous group of disorders characterized by cerebellar atrophy and peripheral sensorimotor neuropathy. Molecular characterization of this group of disorders identified a number of genes contributing to these overlapping phenotypes. Ataxia with oculomotor apraxia type 2 (AOA2) is an autosomal recessive form of ataxia caused by mutations in the SETX gene.

Infantile esotropia could be oligogenic and allelic with Duane retraction syndrome.

Purpose: To describe phenotyping and linkage analysis results for available members from a consanguineous nuclear family with hereditary congenital strabismus.

Methods: Both parents and all 12 children underwent clinical examination. Available affected and several unaffected family members had venous blood sampling for DNA extraction and 10K single nucleotide polymorphism (SNP) genotyping (Affymetrix Gene Chip® Human).

Prolonged pursuit by optokinetic drum testing in asymptomatic female carriers of novel FRMD7 splice mutation c.1050 +5 G>A.

Objective: To determine the genotype underlying suspected X-linked infantile nystagmus in a family and to correlate genotype with clinical examination in potential female carriers.

Methods: Ophthalmic examination (ophthalmic, orthoptic, optokinetic [OKN] drum, and electrophysiologic when possible) and candidate gene analysis.

Results: Two affected brothers had infantile nystagmus with no evidence of associated visual or neurological disease.

Potential linkage of different phenotypic forms of childhood strabismus to a recessive susceptibility locus (16p13.12-p12.3).

Purpose: To perform linkage analysis on an inbred family with members who exhibit different phenotypic forms of childhood strabismus.

Methods: Prospective clinical examination and linkage analysis.

Results: three of the ten siblings and their cousin each had a different phenotypic form of childhood strabismus: infantile esotropia with convergence excess, esotropia associated with anisometropic amblyopia, unilateral esotropic Duane syndrome, and monocular elevation deficiency.

Clinical and molecular characterization of ataxia with oculomotor apraxia patients in Saudi Arabia.

Background: Autosomal recessive ataxias represent a group of clinically overlapping disorders. These include ataxia with oculomotor apraxia type1 (AOA1), ataxia with oculomotor apraxia type 2 (AOA2) and ataxia-telangiectasia-like disease (ATLD). Patients are mainly characterized by cerebellar ataxia and oculomotor apraxia.

Lack of KIF21A mutations in congenital fibrosis of the extraocular muscles type I patients from consanguineous Saudi Arabian families.

Purpose: Congenital fibrosis of the extraocular muscles type I (CFEOM1), the most common CFEOM worldwide, is characterized by bilateral ptotic hypotropia, an inability to supraduct above the horizontal midline, horizontal strabismus (typically exotropia), and ophthalmoplegia with abnormal synkinesis. This distinct non-syndromic phenotype is considered autosomal dominant and is virtually always from heterozygous missense mutations in kinesin family member 21A (KIF21A). However, there are occasional KIF21A-negative cases, opening the possibility for a recessive cause.

Germline Mosaicism for KIF21A Mutation (p.R954L) Mimicking Recessive Inheritance for Congenital Fibrosis of the Extraocular Muscles.

Objective: To document the genotype for familial congenital fibrosis of the extraocular muscles (CFEOM) with apparent autosomal recessive inheritance.

Design: Interventional family study.

Participants: Two affected siblings, 3 asymptomatic siblings, and their 2 asymptomatic parents.

Homozygous mutations in ADAMTS10 and ADAMTS17 cause lenticular myopia, ectopia lentis, glaucoma, spherophakia, and short stature.

Weill-Marchesani syndrome (WMS) is a well-characterized disorder in which patients develop eye and skeletal abnormalities. Autosomal-recessive and autosomal-dominant forms of WMS are caused by mutations in ADAMTS10 and FBN1 genes, respectively. Here we report on 13 patients from seven unrelated families from the Arabian Peninsula.

Bilateral synergistic convergence associated with homozygous ROB03 mutation (p.Pro771Leu).

Objective: To document the phenotype and determine the genotype of a child with synergistic convergence.

Design: Interventional case report.

Participants: Patient and nuclear family (7 members total).