Autosomal Recessive Form (autosomal + recessive_form)

Distribution by Scientific Domains


Selected Abstracts


Hereditary hypophosphatemias: New genes in the bone,kidney axis (Review Article)

NEPHROLOGY, Issue 4 2007
ARMANDO L NEGRI
SUMMARY: Hypophosphatemia due to isolated renal phosphate wasting is a genetically heterogeneous disease. Two new genes linked to two different forms of hereditary hypophosphatemias have recently been described. Autosomal recessive form of hypophosphatemic rickets was mapped to chromosome 4q21 and identified homozygous mutations in dentin matrix protein 1 (DMP1) gene, which encodes a non-collagenous bone matrix protein. Intact plasma levels of the phosphaturic protein FGF23 (fibroblast growth factor 23) were clearly elevated in some of the affected individuals, providing a possible explanation for the phosphaturia and inappropriately normal 1,25(OH)2D levels, and suggesting that DMP1 may regulate FGF23 expression. Hereditary hypophosphatemic rickets with hypercalciuria is another rare disorder of autosomal recessive inheritance. Affected individuals present with hypercalciuria due to increased serum 1,25-dihydroxyvitamin D levels and increased intestinal calcium absorption. The disease was mapped to a 1.6 Mbp region on chromosome 9q34, which contains SLC34A3, the gene encoding the renal sodium-phosphate cotransporter NaPi-IIc. This was the first demonstration that NaPi-IIc has a key role in the regulation of phosphate homeostasis. Thus, DMP1 and NaPi-IIc add two new members to the bone,kidney axis proposed since it was discovered that the first phosphatonin, FGF23, was of osteoblastic/osteocyte origin. This provides a mechanism for the skeleton to communicate with the kidney to coordinate the mineralization of extracelular matrix and the renal handling of phosphate. [source]


Mutations in severe combined immune deficiency (SCID) due to JAK3 deficiency

HUMAN MUTATION, Issue 4 2001
Luigi D. Notarangelo
Abstract During the last 10 years, an increasing number of genes have been identified whose abnormalities account for primary immunodeficiencies, with defects in development and/or function of the immune system. Among them is the JAK3 -gene, encoding for a tyrosine kinase that is functionally coupled to cytokine receptors which share the common gamma chain. Defects of this gene cause an autosomal recessive form of severe combined immunodeficiency with almost absent T-cells and functionally defective B-cells (T,B+ SCID). Herewith, we present molecular information on the first 27 unique mutations identified in the JAK3 gene, including clinical data on all of the 23 affected patients reported so far. A variety of mutations scattered throughout all seven functional domains of the protein, and with different functional effects, have been identified. Availability of a molecular screening test, based on amplification of genomic DNA, facilitates the diagnostic approach, and has permitted recognition that JAK3 deficiency may also be associated with atypical clinical and immunological features. Development of a structural model of the JAK3 kinase domain has allowed characterization of the functional effects of the various mutations. Most importantly, molecular analysis at the JAK3 locus results in improved genetic counseling, allows early prenatal diagnosis, and prompts appropriate treatment (currently based on hematopoietic stem cell transplantation) in affected families. Hum Mutat 18:255,263, 2001. © 2001 Wiley-Liss, Inc. [source]


A Novel Early Onset Lethal Form of Catecholaminergic Polymorphic Ventricular Tachycardia Maps to Chromosome 7p14-p22

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2007
Ph.D., ZAHURUL A. BHUIYAN M.D.
Introduction: Previously, autosomal dominant catecholaminergic polymorphic ventricular tachycardia (CPVT [1]) was mapped to chromosome 1q42,43 with identification of pathogenic mutations in RYR2. Autosomal recessive CPVT (2) was mapped to chromosome 1p13,21, leading to the identification of mutations in CASQ2. In this study, we aimed to elucidate clinical phenotypes of a new variant of CPVT (3) in an inbred Arab family and also delineate the chromosomal location of the gene causing CPVT (3). Methods and Results: In a highly inbred family, clinical symptoms of CPVT appeared early in childhood (7,12 years) and in three of the four cases, the first appearance of symptoms turned into a fatal outcome. Parents of the affected children were first-degree cousins and without any symptoms. Segregation analysis suggested an autosomal recessive inheritance. A genome-wide search using polymorphic DNA markers mapped the disease locus to a 25-Mb interval on chromosome 7p14-p22. A maximal multipoint LOD score of 3.17 was obtained at marker D7S493. Sequencing of putative candidate genes, SP4, NPY, FKBP9, FKBP14, PDE1C, and TBX20, in and around this locus, did not reveal any mutation. Conclusions: We have identified a novel highly malignant autosomal recessive form of CPVT and mapped this disorder to a 25-Mb interval on chromosome 7p14-p22. [source]


Evaluation of RDS/Peripherin and ROM1 as candidate genes in generalised progressive retinal atrophy and exclusion of digenic inheritance

ANIMAL GENETICS, Issue 3 2000
M Runte
Summary Generalised progressive retinal atrophy (gPRA) is a heterogeneous group of hereditary diseases causing degeneration of the retina in dogs and cats. As a combination of mutations in theRDS/Peripherin and the ROM1 genes leads to the phenotype of retinitis pigmentosa in man we first performed mutation analysis to screen these genes for disease causing mutations followed by the investigation of a digenic inheritance in dogs. We cloned the RDS/Peripherin gene and investigated the RDS/Peripherin and ROM1 genes for disease causing mutations in 13 gPRA-affected dog breeds including healthy animals, obligate gPRA carriers and gPRA-affected dogs. We screened for mutations using single strand conformation polymorphism (SSCP) analysis. Sequence analysis revealed several sequence variations. In the coding region of the RDS/Peripherin gene three nucleotide exchanges were identified (A277C; C316T; G1255A), one of which leads to an amino acid substitution (Ala339Thr). Various silent sequence variations were found in the coding region of the ROM1 gene (A536G, G1006A, T1018C, T1111C, C1150T, C1195T), as well as an amino acid substitution (G252T; Ala54Ser). By excluding the respective gene as a cause for gPRA several sequence variations in the intronic regions were investigated. None of these sequence variations cosegregated with autosomal recessively (ar) transmitted gPRA in 11 breeds. The candidate geneRDS/Peripherin obviously does not harbour the critical mutation causing the autosomal recessive form of gPRA because diseased individuals show heterozygous genotypes for sequence variations in the Miniature Poodle, Dachshund, Australian Cattle Dog, Cocker Spaniel, Chesapeake Bay Retriever, Entlebucher Sennenhund, Sloughi, Yorkshire Terrier, Tibet Mastiff, Tibet Terrier and Labrador Retriever breeds. In the following breeds the ROM1 gene was also excluded indirectly for gPRA: Miniature Poodle, Dachshund, Australian Cattle Dog, Sloughi, Collie, Tibet Terrier, Labrador Retriever and Saarloos/Wolfhound. Digenic inheritance for gPRA is practically excluded for both these genes in four breeds: Miniature Poodle, Dachshund, Labrador Retriever and Saarloos/Wolfhound. [source]


A novel deletion mutation in LIPH gene causes autosomal recessive hypotrichosis (LAH2)

CLINICAL GENETICS, Issue 2 2008
M Jelani
Autosomal recessive hypotrichosis is a rare hereditary disorder characterized by sparse hair on scalp and rest of the body of affected subjects. Recently, three clinically similar autosomal recessive forms of hypotrichosis [localized autosomal recessive hypotrichosis (LAH)1], LAH2 and LAH3 have been mapped on chromosomes 18q12.1, 3q27.3, and 13q14.11-q21.32, respectively. For these three loci, two genes DSG4 for LAH1 and LIPH for LAH2 have been identified. To date, only five mutations in DSG4 and two in LIPH genes have been reported. In this study, we have ascertained two large unrelated consanguineous Pakistani families with autosomal recessive form of hypotrichosis. Affected individuals showed homozygosity to the microsatellite markers tightly linked to LIPH gene on chromosome 3q27. Sequence analysis of the gene in the affected subjects from both the families revealed a novel deletion mutation in exon 5 (c.659-660delTA) causing frameshift and downstream premature termination codon. All the three mutations identified in the LIPH gene, including the one in this study, are deletion mutations. [source]


Novel COL4A5, COL4A4, and COL4A3 mutations in Alport syndrome,,

HUMAN MUTATION, Issue 1 2005
Mato Nagel
Abstract This study summarizes 47 novel mutations identified during routine molecular diagnostics for Alport syndrome. We detected 34 in COL4A5, the gene responsible for X-linked Alport syndrome, and 13 in COL4A3 and COL4A4, the genes responsible for autosomal recessive Alport syndrome. A high detection rate of 90% was achieved among patients with typical clinical symptoms and a characteristic family history in both X-linked and autosomal recessive forms, and it can be assumed that most relevant mutations have been identified. In numerous positively tested patients, genetic variations which are unknown were detected. © 2005 Wiley-Liss, Inc. [source]


Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 65

JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2003
E Bellone
Mutations in a gene encoding a novel protein of unknown function, the ganglioside-induced differentiation-associated protein 1 gene (GDAP1), are associated with one of the autosomal recessive forms of Charcot-Marie-Tooth disease (CMT4A). Mutations in GDAP1 can cause both axonal and demyelinating inherited peripheral neuropathies. The GDAP1 gene maps on chromosome 8q21.1, encompassing 13.9 kb of genomic DNA. The coding sequence is comprised of six exons. Little is known about the function of GDAP1. The mouse homologue Gdap1 is highly expressed in brain. Northern-blot analysis showed that GDAP1 is also expressed in peripheral nerves, both in neurons and in Schwann cells. A series of Italian patients with demyelinating (n = 42) and axonal (n = 39) peripheral neuropathy with possible recessive inheritance was screened for mutations in the GDAP1 gene. The entire coding region, including exon-intron boundaries, was examined by single strand conformation polymorphism (SSCP) and direct sequencing. All patients were negative for the 17p11.2 duplication and for mutations in the MPZ, GJB1, PMP22 and EGR2 genes. SSCP analysis showed a few electrophoretic variants, in the exon 1, exon 3 and exon 4, respectively. Direct sequencing demonstrated the presence of a common single nucleotide polymorphism in the exon 4 (c.507T > G) and a nucleotide substitution in the exon 3. The latter was found in four patients, belonging to three families, and was not detected in a series of normal subjects. Further studies are in progress to evaluate the possible role of this variant in the pathophysiology of the disease. This work was partially supported by grants MURST 2000 to F.A. and Ministero della Sanitŕ to P.M. [source]


Extensive Tinea in a Patient With Severe Combined Immunodeficiency

PEDIATRIC DERMATOLOGY, Issue 2 2009
RAFAEL JIMÉNEZ-PUYA M.D.
Although the X-linked recessive form is most common (60,70%), there are autosomal recessive forms (20%) and spontaneous mutations. While SCID may present with many nosocomial infections, dermatophyte infections are not common. We reported a case of SCID which was associated with a widespread skin infection with Trichophyton mentagrophytes. [source]


A novel deletion mutation in LIPH gene causes autosomal recessive hypotrichosis (LAH2)

CLINICAL GENETICS, Issue 2 2008
M Jelani
Autosomal recessive hypotrichosis is a rare hereditary disorder characterized by sparse hair on scalp and rest of the body of affected subjects. Recently, three clinically similar autosomal recessive forms of hypotrichosis [localized autosomal recessive hypotrichosis (LAH)1], LAH2 and LAH3 have been mapped on chromosomes 18q12.1, 3q27.3, and 13q14.11-q21.32, respectively. For these three loci, two genes DSG4 for LAH1 and LIPH for LAH2 have been identified. To date, only five mutations in DSG4 and two in LIPH genes have been reported. In this study, we have ascertained two large unrelated consanguineous Pakistani families with autosomal recessive form of hypotrichosis. Affected individuals showed homozygosity to the microsatellite markers tightly linked to LIPH gene on chromosome 3q27. Sequence analysis of the gene in the affected subjects from both the families revealed a novel deletion mutation in exon 5 (c.659-660delTA) causing frameshift and downstream premature termination codon. All the three mutations identified in the LIPH gene, including the one in this study, are deletion mutations. [source]