Search results for " Mutation"

Identification of two novel polymorphisms and a rare deletion variant in the human dopamine D4 receptor gene

1995

We report two novel polymorphisms and a rare deletion variant in the human dopaine D4 receptor gene. The two polymorphisms are characterized by single base pair substitutions, namely a G-->C transversion changing codon 11 from GGG (encoding Gly) to CGG (encoding Arg) and a C-->T transition in position -11 upstream from the start codon. The Arg11 variant occurs at a frequency of about 1% and the C-->T transition at a frequency of about 7% in German control subjects (n = 148). Allele frequencies observed in patients suffering from schizophrenia (n = 256) and bipolar affective disorder (n = 99) were similar. The deletion variant is characterized by a 21 bp deletion affecting codons 36 to 42 co…

A Novel Loss-of-Function Mutation (N48K) in the PTEN Gene in a Spanish Patient with Cowden Disease

2003

Cowden disease, also known as multiple hamartoma syndrome, is a rare disease inherited in an autosomal dominant pattern, which confers a high risk of developing breast and thyroid carcinomas. Mutations in PTEN, a tumor suppressor gene located on chromosome 10q23, have been identified in patients with Cowden disease. In this work, the direct sequencing of all coding regions of the PTEN gene led us to the identification of N48K, a new germline PTEN missense mutation, in a patient suffering from Cowden disease. The genetic analysis of 200 chromosomes from healthy individuals revealed that the variant was not common in our population. Moreover, by functional analysis we found that the ability o…

Wilms' tumor in patients with 9q22.3 microdeletion syndrome suggests a role for PTCH1 in nephroblastomas

2012

Nephroblastoma (Wilms' tumor; WT) is the most common renal tumor of childhood. To date, several genetic abnormalities predisposing to WT have been identified in rare overgrowth syndromes. Among them, abnormal methylation of the 11p15 region, GPC3 and DIS3L2 mutations, which are responsible for Beckwith-Wiedemann, Simpson-Golabi-Behmel and Perlman syndromes, respectively. However, the underlying cause of WT remains unknown in the majority of cases. We report three unrelated patients who presented with WT in addition to a constitutional 9q22.3 microdeletion and dysmorphic/overgrowth syndrome. The size of the deletions was variable (ie, from 1.7 to 8.9 Mb) but invariably encompassed the PTCH1 …

Congenital neutropenia with retinopathy, a new phenotype without intellectual deficiency or obesity secondary toVPS13Bmutations

2013

Over one hundred VPS13B mutations are reported in Cohen syndrome (CS). Most cases exhibit a homogeneous phenotype that includes intellectual deficiency (ID), microcephaly, facial dysmorphism, slender extremities, truncal obesity, progressive chorioretinal dystrophy, and neutropenia. We report on a patient carrying two VPS13B splicing mutations with an atypical phenotype that included microcephaly, retinopathy, and congenital neutropenia, but neither obesity nor ID. RNA analysis of the IVS34+2T_+3AinsT mutation did not reveal any abnormal splice fragments but mRNA quantification showed a significant decrease in VPS13B expression. RNA sequencing analysis up- and downstream from the IVS57+2T>C…

A novel mutation of the extracellular matrix protein 1 gene (ECM1) in a patient with lipoid proteinosis (Urbach-Wiethe disease) from Sicily

2005

Summary Background  Lipoid proteinosis (LP), also known as Urbach–Wiethe disease, is a rare autosomal recessive disorder characterized by a hoarse voice, warty skin infiltration and scarring. Mutations within the extracellular matrix protein 1 (ECM1) gene cause LP. Objectives  We report the molecular analysis of the ECM1 gene in a Sicilian patient with LP in order to extend the mutation spectrum of this genodermatosis. Methods  We studied a 32-year-old female born from consanguineous parents who was diagnosed at the age of 11 years as having LP. She has a clinical phenotype corresponding to Urbach–Wiethe disease characterized by papules/nodules, indurated plaques and sometimes ulcerated les…

Identification of D179H, a novel missense GJB2 mutation in a Western Sicily family

2013

The main purpose of this study was to describe a novel missense mutation (p.D179H) found in a Western Sicily family and to examine the genetic and audiologic profiles of all family members by performing a GJB2 and GJB6 mutations analysis and a complete audiologic assessment. The proband was a 3-month-old infant with a congenital profound sensorineural hearing loss; direct sequencing of the GJB2 revealed the presence of a c.35delG mutation in the heterozygous state and a heterozygous G[C transition at nucleotide 535 in trans; this novel mutation, called p.D179H, resulted in an aspartic acid to histidine change at codon 179. It was also evidenced in the heterozygous state in two members of th…

Six novel mutations of the LDL receptor gene in FH kindred of Sicilian and Paraguayan descent

2006

Familial hypercholesterolemia (FH) is an autosomal dominant inherited disease caused by mutations in the gene coding for the low density lipoprotein receptor (LDL-R). It is characterized by a high concentration of low density lipoprotein (LDL), which frequently gives rise to premature coronary artery disease. We studied the probands of five FH Sicilian families with 'definite' FH and one proband of Paraguayan descent with homozygous FH who has been treated with an effective living-donor liver transplantation. In order to seek the molecular defect in these six families, we used direct sequencing to define the molecular defects of the LDL-R gene responsible for the disease. We described three…

Association study of a SNP coding for a M129V substitution in the prion protein in schizophrenia.

2003

Prenatal diagnosis of a rhodopsin mutation using chemical cleavage of the mismatch

2002

Objective: Mutations of the rhodopsin gene are responsible for autosomal dominant or recessive retinitis pigmentosa (RP). The present study reports the first prenatal diagnosis performed on chorionic villi biopsy of a pregnant woman affected by a severe form of autosomal dominant transmitted RP, due to the Arg135Trp substitution. Methods: The rhodopsin gene was analysed by automated direct sequencing and, for the first time, by fluorescence-assisted mismatch analysis (FAMA). The latter is an inexpensive, rapid and particularly sensitive method, based on the chemical cleavage of the mismatch in heteroduplex DNA molecules marked with strand-specific fluorophores. Results: FAMA is a feasible p…

The response of autologous T cells to a human melanoma is dominated by mutated neoantigens

2005

Our understanding of pathways leading to antitumor immunity may depend on an undistorted knowledge of the primary antigenic targets of patients' autologous T cell responses. In the melanoma model derived from patient DT, we applied cryopreserved short-term autologous mixed lymphocyte–tumor cell cultures (MLTCs) in combination with an IFN-γ enzyme-linked immunospot (ELISPOT) assay to cDNA expression screening. We identified three previously unknown peptides processed from melanosomal proteins tyrosinase (presented by HLA-A*2601 and -B*3801) and gp100 (presented by HLA-B*07021) and five neoantigens generated by somatic point mutations in the patient's melanoma. The mutations were found in the…