Dataset Information

Factors Affecting Phenotype Variability in a Family with CMT2B: Gender and LRSAM1 Genotype.

ABSTRACT: Charcot-Marie-Tooth disease type 2 (CMT2) is an autosomal dominant axonal neuropathy caused by mutations in various genes. The subtype CMT2B results from missense mutations in RAB7A, member RAS oncogene family gene, whereas missense mutations in the Leucine-rich repeat and sterile alpha motif-containing protein 1 (LRSAM1) gene cause CMT2P. We describe the genotype/phenotype analysis of a family in which a previously described mutation in the RAB7A gene and a novel mutation in the LRSAM1 gene were identified. In this family, none of the individuals had ulceromutilating features, and there was a marked variability in the age of onset. We discuss the possible etiology of the observed phenotypic variability including the role of gender and possible RAB7A/LRSAM1 gene interactions.

SUBMITTER: Peddareddygari LR

PROVIDER: S-EPMC4939679 | biostudies-literature | 2016 May-Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Factors Affecting Phenotype Variability in a Family with CMT2B: Gender and LRSAM1 Genotype.

Peddareddygari Leema Reddy LR Oberoi Kinsi K Vellore Jaasrini Reddy JR Grewal Raji P RP

Case reports in neurology 20160501 2

Charcot-Marie-Tooth disease type 2 (CMT2) is an autosomal dominant axonal neuropathy caused by mutations in various genes. The subtype CMT2B results from missense mutations in RAB7A, member RAS oncogene family gene, whereas missense mutations in the Leucine-rich repeat and sterile alpha motif-containing protein 1 (LRSAM1) gene cause CMT2P. We describe the genotype/phenotype analysis of a family in which a previously described mutation in the RAB7A gene and a novel mutation in the LRSAM1 gene wer ...[more]

PMID: 27462242

Similar Datasets

Project description:AimTo investigate genotype-phenotype correlations in patients with perianal Crohn's disease (PCD) in order to determine which factors predispose to development of perianal disease in Crohn's patients.MethodsSeven-hundred and ninety-five Caucasian individuals (317 CD patients and 478 controls without inflammatory bowel disease, IBD) were prospectively enrolled into a clinical/genetic database. Demographic and clinical data, as well as peripheral blood leukocyte DNA were obtained from all patients. The following were evaluated: three NOD2/CARD15 polymorphisms: R702W, G908R, and 1007insC; five IL-23r risk alleles: rs1004819, rs10489629, rs2201841, rs11465804, and rs11209026; a well-characterized single-nucleotide polymorphism (SNP) on the IBD5 risk haplotype (OCTN1) and two peripheral tag SNPs (IGR2060 and IGR3096).ResultsPCD occurred in 147 (46%) of CD patients. There was no significant difference in the age at disease diagnosis between non-PCD and PCD patients (33 vs. 29 years, respectively). PCD patients were more likely to have disease located in the colon and ileocolic regions (79 PCD vs. 57% non-PCD; n = 116 vs. n = 96; p < 0.001), whereas patients with non-PCD were more likely to have Crohn's within the terminal ileum and upper gastrointestinal tract (43% non-PCD vs. 21% PCD; n = 73 vs. n = 31; p < 0.05). Thirty-four percent of patients with PCD required a permanent ileostomy (n = 50) compared to only 4% of non-PCD patients (n = 6; p < 0.05). Mutations in CARD15/NOD2 and IL-23r were risk factors for CD overall; however, in contrast to prior reports, in this patient population, OCTN1 and IGR variations within the IBD5 haplotype were not significant predictors of PCD.ConclusionColon/ileocolic CD location appears to be a significant predictor of perianal manifestations of CD. Patients with PCD are more likely to require permanent fecal diversion. We did not identify any genetic variations or combination of clinical findings and genetic variations within the CARD15/NOD2, IL-23r, and OCTN1 genes or IGR that were predictive of PCD.

Project description:PurposeInvestigate in vivo cone photoreceptor structure in familial aniridia caused by deletion in the PAX6 gene to elucidate the complexity of between-individual variation in retinal phenotype.DesignDescriptive case-control study.ParticipantsEight persons with congenital aniridia (40-66 yrs) from 1 family and 33 normal control participants (14-69 yrs), including 7 unaffected family members (14-53 yrs).MethodsDNA was isolated from saliva samples and used in polymerase chain reaction analysis to amplify and sequence exons and intron or exon junctions of the PAX6 gene. High-resolution retinal images were acquired with OCT and adaptive optics scanning light ophthalmoscopy. Cone density (CD; in cones per square millimeter) and mosaic regularity were estimated along nasal-temporal meridians within the central 0° to 5° eccentricity. Horizontal spectral-domain OCT line scans were segmented to analyze the severity of foveal hypoplasia (FH) and to measure retinal layer thicknesses.Main outcomes and measuresWithin-family variability in macular retinal layer thicknesses, cone photoreceptor density, and mosaic regularity in aniridia compared with normal control participants.ResultsDNA sequencing revealed a known PAX6 mutation (IV2-2delA). Those with aniridia showed variable iris phenotype ranging from almost normal appearance to no iris. Four participants with aniridia demonstrated FH grade 2, 2 demonstrated grade 3 FH, and 1 demonstrated grade 4 FH. Visual acuity ranged from 0.20 to 0.86 logarithm of the minimum angle of resolution. Adaptive optics scanning light ophthalmoscopy images were acquired from 5 family members with aniridia. Foveal CD varied between 19 899 and 55 128 cones/mm2 with overlap between the foveal hypoplasia grades. Cone density was 3 standard deviations (SDs) or more less than the normal mean within 0.5°, 2 SDs less than the normal mean at 0.5° to 4°, and more than 1 SD less than the normal mean at 5° retinal eccentricity.ConclusionsThe results showed considerable variability in foveal development within a family carrying the same PAX6 mutation. This, together with the structural and functional variability within each grade of foveal hypoplasia, underlines the importance of advancing knowledge about retinal cellular phenotype in aniridia.

Dataset Information

Factors Affecting Phenotype Variability in a Family with CMT2B: Gender and LRSAM1 Genotype.

Publications

Factors Affecting Phenotype Variability in a Family with CMT2B: Gender and LRSAM1 Genotype.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets