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K B Jedele

Publications and source records attributed to K B Jedele.

11 recordsLinked to original sources
PubMed1998

Spinal and bulbar muscular atrophy (SBMA): somatic stability of an expanded CAG repeat in fetal tissues.

Spinal and bulbar muscular atrophy (SBMA) is a rare X-linked motor neuron degenerative disease caused by an expanded trinucleotide repeat. Unlike most other trinucleotide repeat diseases, SBMA shows limited meiotic instability, and evidence thus far indicates absence of somatic instability in adults. Data regarding the presence of fetal tissue somatic mosaicism is unavailable. We present a family in which a woman whose father had SBMA requested prenatal testing. After informed consent. molecular genetic evaluation showed the male fetus to carry the SBMA repeat elongation. Testing of fetal tissues after elective pregnancy termination showed no somatic mosaicism in the CAG repeat length. This is the first report of molecular genetic analysis of multiple tissues in an affected fetus, and only the second report of prenatal diagnosis in SBMA.

Abortion, Induced↗
PubMed1998

A systematic mutation screen of 10 nuclear and 25 mitochondrial candidate genes in 21 patients with cytochrome c oxidase (COX) deficiency shows tRNA(Ser)(UCN) mutations in a subgroup with syndromal encephalopathy.

COX deficiency is believed to be the most common defect in neonates and infants with mitochondrial diseases. To explore the causes of this group of disorders, we examined 25 mitochondrial genes (three COX subunit genes and 22 tRNA genes) and 10 nuclear COX subunit genes for disease associated mutations using PCR-SSCP and direct sequencing of polymorphic SSCP fragments. DNA from one patient with severe COX deficiency and with consanguineous parents was entirely sequenced. The patient population consisted of 21 unrelated index patients with mitochondrial disorders and predominant (n=7) or isolated (n=14) COX deficiency. We detected two distinct tRNA(Ser)(UCN) mutations, which have been recently described in single kindreds, in a subgroup of four patients with COX deficiency, deafness, myoclonic epilepsy, ataxia, and mental retardation. Besides a number of nucleotide variants, a single novel missense mutation, which may contribute to the disease phenotype, was found in the mitochondrial encoded COX 1 gene (G6480A). Mutations in nuclear encoded COX subunit genes were not detected in this study.

Adolescent↗
PubMed1998

Mutation screening of the BTK gene in 56 families with X-linked agammaglobulinemia (XLA): 47 unique mutations without correlation to clinical course.

OBJECTIVES: To determine the utility of single-stranded conformation polymorphism (SSCP) analysis for mutation screening in the BTK (Bruton's tyrosine kinase) gene, we investigated 56 X-linked agammaglobulinemia (XLA) families. To obtain genotype/ phenotype correlations, predicted protein aberrations were correlated with the clinical course of the disease. PATIENTS: This study included 56 patients with XLA, with or without a positive family history, who were diagnosed on the basis of their clinical features, low peripheral B-cell count, and low immunoglobulin levels. Ten patients with isolated hypogammaglobulinemia and 50 healthy males served as controls. METHODS: SSCP analysis was performed for the entire BTK gene, including the exon-intron boundaries and the promoter region. Structural implications of the missense mutations were investigated by molecular modeling, and the functional consequences of some mutations also were evaluated by in vitro kinase assays and Western blot analysis. RESULTS: We report the largest series of patients with XLA to date. All but 5 of the 56 index patients with XLA screened with SSCP analysis showed BTK gene abnormalities, and in 2 of the 5 SSCP-negative patients, no BTK protein was found by Western blot analysis. There were 51 mutations, including 37 novel ones, distributed across the entire gene. This report contains the first promoter mutation as well as 14 novel missense mutations with the first ones described for the Tec homology domain and the glycine-rich motif in the SH1 domain. Each index patient had a different mutation, except for four mutations, each in two unrelated individuals. This result supports the strong tendency for private mutations in this disease. No mutations were found in the controls. CONCLUSIONS: Our results demonstrate that molecular genetic testing by SSCP analysis provides an accurate tool for the definitive diagnosis of XLA and the discrimination of borderline cases, such as certain hypogammaglobulinemia or common variable immunodeficiency patients with overlapping clinical features. Genotype/ phenotype correlations are not currently possible, making prediction of the clinical course based on molecular genetic data infeasible.

Adolescent↗
PubMed1996

Discordant monozygotic twins with the Schimmelpenning-Feuerstein-Mims syndrome.

The Schimmelpenning-Feuerstein-Mims syndrome (SFM), characterized by linear nevus sebaceous and ocular and neurologic abnormalities, is a sporadic condition without known familial cases or etiology. We report the occurrence of SFM in only one of two monozygotic (MZ) twins. After considering a variety of possible causative mechanisms, we suggest that a postzygotic dominant lethal mutation in mosaic form may best explain SFM and the discordancy for SFM in these MZ twins.

Abnormalities, Multiple↗
PubMed1996

FRAXE testing.

Explore the source record for details and available documents.

Female↗
PubMed1992

Velo-cardio-facial syndrome associated with ventricular septal defect, pulmonary atresia, and hypoplastic pulmonary arteries.

We report on 15 patients with velo-cardiofacial syndrome who had a severe form of tetralogy of Fallot (pulmonary atresia, ventricular septal defect, and hypoplastic pulmonary arteries). Noncardiac anomalies in these patients included typical facial and ear anomalies in 15, nasal speech in 13, palate anomalies in 10, and developmental delay in 10. Seven patients had significant bronchospasm, which has not been reported in association with the velo-cardio-facial syndrome. All 15 patients had severe abnormalities of the arborization of the pulmonary arterial tree, which also has not been reported in velo-cardio-facial syndrome. All patients underwent staging operations to prepare the true pulmonary vascular tree for complete repair of the defect (five underwent complete repair and three survived). Of the remaining 10 patients, 6 are awaiting further operation, 3 are not candidates for complete repair, and 1 has died.

Abnormalities, Multiple↗
PubMed1991

Familial dermographism.

Urticaria in response to various physical stimuli has been reported in sporadic and familial patterns. The most common of these physical urticarias, dermographism, is a localized urticarial response to stroking or scratching of the skin and has not been reported previously to be familial. A four-generation family with dermographism, probably inherited as an autosomal dominant trait, is presented along with a discussion of sporadic dermographism and other types of familial physical urticarias.

Adult↗
PubMed1990

Frequency of congenital heart defects in patients with hemophilia.

Most structural congenital heart defects (CHD) are thought to be multifactorially determined, but the precise causal factors usually are unknown. One may postulate that vascular events, such as hemorrhage in the developing embryo, could influence morphogenesis of the heart. One method of studying this hypothesis is to determine the frequency of CHD in persons with heritable bleeding diatheses and their families. We reviewed retrospectively medical and family histories of 120 hemophilia A and 14 hemophilia B patients seen in our Genetics Department. The family histories included 1,126 maternal relatives of hemophiliac patients. We also reviewed the family histories of 138 patients with X-linked disorders who did not have bleeding diatheses or syndromes associated with CHD; these histories included 960 maternal relatives. There was one confirmed case of a CHD in 134 hemophilia patients, giving a frequency of 0.75% compared to 0.8% in the general population at birth. There was no apparent difference in the frequency of CHD in hemophilia A and B patients compared to the general population or in the relatives of hemophilia patients as compared to control individuals.

Female↗
PubMedDate not supplied

Linkage of nonspecific X-linked mental retardation to Xq21.31.

Mental retardation unassociated with the Fragile X syndrome accounts for up to 60% of patients with X-linked mental retardation. In this investigation, we report on a family with mild non-specific X-linked mental retardation (MRX) without other apparent phenotypic abnormalities. Linkage analysis on 27 relatives using 18 polymorphic markers spanning the X-chromosome demonstrated close linkage to DXYS1 with a peak LOD score of 2.14 at a theta of 0. Numerous families with various types of MRX have now been studied by other investigators using molecular genetic techniques. In addition to the family described in this report, a number of these have demonstrated linkage to the DXYS1 locus. These data suggest that a gene for mental retardation may exist in the region of DXYS1. Alternatively, this area of the X-chromosome may harbor multiple different but closely linked genes which cause the various types of MRX.

Adolescent↗
PubMedDate not supplied

UHX1 and PCTK1: precise characterisation and localisation within a gene-rich region in Xp11.23 and evaluation as candidate genes for retinal diseases mapped to Xp21.1-p11.2.

The gene for ubiquitin hydrolase on the X chromosome (UHX1), cloned and mapped to Xp21.2-p11.2, is a candidate gene for retinal diseases. We used fine mapping techniques to localise UHX1 between markers DXS1266 and DXS337, where congenital stationary night blindness (XICSNB) and retinitis pigmentosa type 2 (RP2) are also located. Reevaluation of the UHX1 gene structure demonstrated five new exons, for a total of 21 exons and a predicted protein product of 963 amino acids. Evaluation of patients revealed no UHX1 mutations using SSCP (10 CSNB1 and 20 XLRP) or deletion screening with cDNA hybridisation (13 CSNB1 and 43 XLRP). Likewise, no aberrations were found in the nearby PCTAIRE1 (PCTK1) gene in 13 CSNB1 and 43 XLRP patients by deletion screening. Thus mutations of UHX1, and probably PCTK1, do not appear to cause common X-linked eye diseases. UHX1's role in patients with mental retardation may be appropriate for further investigations into UHX1 function.

Base Sequence↗