An association study of 22 candidate genes in psoriasis families reveals shared genetic factors with other autoimmune and skin disorders.

Psoriasis is a common inflammatory and hyperproliferative skin disease. Recent studies have reported that common genetic factors may underlie both skin and immune-mediated disorders. We hypothesized that such genes may be involved in susceptibility to psoriasis, and undertook an association analysis of 22 candidate genes in a set of French high-risk psoriasis families.

ADAM33, a new candidate for psoriasis susceptibility.

Psoriasis is a chronic skin disorder with multifactorial etiology. In a recent study, we reported results of a genome-wide scan on 46 French extended families presenting with plaque psoriasis. In addition to unambiguous linkage to the major susceptibility locus PSORS1 on Chromosome 6p21, we provided evidence for a susceptibility locus on Chromosome 20p13.

Confirmation of psoriasis susceptibility loci on chromosome 6p21 and 20p13 in French families.

Plaque psoriasis is a chronic inflammatory disorder of the skin. It is inherited as a multifactorial trait, with a strong genetic component. Linkage studies have identified a large number of disease loci, but very few could be replicated in independent family sets.

Exploration of the genetic architecture of idiopathic generalized epilepsies.

Purpose: Idiopathic generalized epilepsy (IGE) accounts for approximately 20% of all epilepsies and affects about 0.2% of the general population. The etiology of IGE is genetically determined, but the complex pattern of inheritance suggests an involvement of a large number of susceptibility genes.

Linkage analysis and disease models in benign familial infantile seizures: a study of 16 families.

Purpose: Benign familial infantile seizures (BFIS) is a genetically heterogeneous condition characterized by partial seizures, onset age from 3 to 9 months, and favorable outcome. BFIS loci were identified on chromosomes 19q12-13.1 and 16p12-q12, allelic to infantile convulsions and choreathetosis.

Mutations in a new cytochrome P450 gene in lamellar ichthyosis type 3.

We report the identification of mutations in a non-syndromic autosomal recessive congenital ichthyosis (ARCI) in a new gene mapping within a previously identified locus on chromosome 19p12-q12, which has been defined as LI3 in the OMIM database (MIM 604777). The phenotype usually presents as lamellar ichthyosis and hyperlinearity of palms and soles. Seven homozygous mutations including five missense mutations and two deletions were identified in a new gene, FLJ39501, on chromosome 19p12 in 21 patients from 12 consanguineous families from Algeria, France, Italy and Lebanon.

L-2-Hydroxyglutaric aciduria: identification of a mutant gene C14orf160, localized on chromosome 14q22.1.

l-2-Hydroxyglutaric aciduria (l-2-HGA) is characterized by progressive deterioration of central nervous system function including epilepsy and macrocephaly in 50% of cases, and elevated levels of l-2-hydroxyglutaric acid in urine, blood and cerebrospinal fluid (CSF). Nuclear magnetic resonance imaging shows distinct abnormalities. We report the identification of a gene for l-2-HGA aciduria (MIM 236792) using homozygosity mapping.

Mutations in ichthyin a new gene on chromosome 5q33 in a new form of autosomal recessive congenital ichthyosis.

We report the genomic localization by homozygosity mapping and the identification of a gene for a new form of non-syndromic autosomal recessive congenital ichthyosis. The phenotype usually presents as non-bullous congenital ichthyosiform erythroderma with fine whitish scaling on an erythrodermal background; larger brownish scales are present on the buttocks, neck and legs. A few patients presented a more generalized lamellar ichthyosis.

Infantile convulsions and paroxysmal choreoathetosis in a consanguineous family.

Infantile convulsions and paroxysmal choreoathetosis is a rare autosomal-dominant disorder characterized by variable presentation of benign infantile seizures and paroxysmal dyskinesia. The disease gene was mapped to chromosome 16p12-q12. We report a consanguineous Turkish family with three individuals affected by infantile convulsions and paroxysmal choreoathetosis.

Mutations in the transporter ABCA12 are associated with lamellar ichthyosis type 2.

Lamellar ichthyosis type 2 (LI2) is a rare autosomal recessive skin disorder for which a gene has been localized on chromosome 2q33-35. We report the identification of five missense mutations in the ABCA12 gene in nine families from Africa affected by LI2. The mutations were homozygous in eight consanguineous families and heterozygous in one non-consanguineous family.

Identification of mutations in a new gene encoding a FERM family protein with a pleckstrin homology domain in Kindler syndrome.

Kindler syndrome is a rare autosomal-recessive genodermatosis characterized by bullous poikiloderma with photosensitivity. We report the localization to chromosome 20p12.3 by homozygosity mapping and the identification of a new gene, which we propose to name kindlerin.

Novel mutations in the gene encoding secreted lymphocyte antigen-6/urokinase-type plasminogen activator receptor-related protein-1 (SLURP-1) and description of five ancestral haplotypes in patients with Mal de Meleda.

Mal de Meleda is a recessive, transgressive palmoplantar keratoderma for which we previously identified mutations in the gene encoding secreted lymphocyte antigen-6/urokinase-type plasminogen activator receptor-related protein-1 (SLURP-1). In this report we describe two new mutations: (i) a founder mutation, which changes a conserved cysteine residue to tyrosine (C99Y) in a large inbred Tunisian pedigree, and (ii) a signal sequence mutation (W15R), which was homozygous in a German family and heterozygous in a Scottish patient. Four ancestral haplotypes were observed in 69 patients from countries around the Mediterranean basin, and an additional haplotype was found in the German and Scottish patients.

Exploration of a putative susceptibility locus for idiopathic generalized epilepsy on chromosome 8p12.

Purpose: A recent genome-wide scan revealed a major susceptibility locus for idiopathic generalized epilepsies (IGEs) in the chromosomal region 8p12 in 32 IGE families without members with juvenile myoclonic epilepsy (JME). This study explored the presence of an IGE locus in the chromosomal region 8p12.

Methods: Our study included 176 multiplex families of probands with common IGE syndromes.

A locus for simple pure febrile seizures maps to chromosome 6q22-q24.

Febrile seizures (FS) syndromes exhibit major clinical and genetic heterogeneity. We report a clinical and genetic study of three families with simple FS segregating as an autosomal dominant (AD) trait with high penetrance. All affected members presented a homogeneous phenotype of simple FS.

No evidence for a susceptibility locus for idiopathic generalized epilepsy on chromosome 18q21.1.

A recent genome-wide scan showed strong evidence for a major locus for common syndromes of idiopathic generalized epilepsy (IGE) at the marker D18S474 on chromosome 18q21.1 (LOD score 4.5/5.

Physicians' response to a letter to confirm diagnosis in a genetic study of psoriasis.

Context. Phenotyping of diseases is essential for genetic studies. In common diseases like psoriasis, the co-operation of family practitioners is helpful to confirm the phenotype of the patients.

Lipoxygenase-3 (ALOXE3) and 12(R)-lipoxygenase (ALOX12B) are mutated in non-bullous congenital ichthyosiform erythroderma (NCIE) linked to chromosome 17p13.1.

We report the identification of mutations in lipoxygenase-3 (ALOXE3) and 12(R)-lipoxygenase (ALOX12B) genes in non-bullous congenital ichthyosiform erythroderma (NCIE) linked to chromosome 17. Linkage disequilibrium analysis of six families affected by NCIE permitted us to reduce a recently reported interval of 8.4 cM on chromosome 17p13.