PubMed Health⌕ Search

Biomedical subjects

Peter Hedera

Publications and source records attributed to Peter Hedera.

23 records · Page 2Linked to original sources

The second kindred with autosomal dominant distal myopathy linked to chromosome 14q: genetic and clinical analysis.

BACKGROUND: Distal myopathies (MPDs) are genetically heterogeneous. Genetic causes within this subgroup of muscle disorders remain largely unknown. An MPD linked to chromosome 14q11-q13 (MPD1) is rare, and to our knowledge, only one family with definitive linkage has been described. OBJECTIVE: To describe the results of clinical and genetic analysis of the second kindred with MPD1. PATIENTS AND METHODS: We have identified a family with an MPD segregating in an autosomal dominant fashion. We tested linkage to previously identified genetic loci on chromosomes 2p, 2q, and 14q. The coding sequence of PABP2 (the polyadenylate-binding protein 2 gene) was analyzed. RESULTS: Every affected individual had selective weakness of foot extensors, with the average age of symptom onset at 20 years. Some patients also had proximal weakness, but none had signs of finger or hand extensor muscle involvement, even in advanced stages of the disease. Two typically affected individuals had signs of idiopathic dilated cardiomyopathy. Genetic analysis detected a tight linkage to chromosome 14q11-q13. Recombination at the telomeric end of the 14q11-q13 locus was found in an unaffected individual who was not considered to be at risk, potentially reducing the locus interval by 2 centimorgans. No mutations in the PABP2 gene were identified. CONCLUSIONS: To our knowledge, our described family is only the second known kindred with a chromosome 14-linked MPD in whom the linkage has been unequivocally established. We did not detect signs of involvement of hand or finger extensors and neck muscles, seen in the original family with MPD1. The degree and frequency of proximal weakness seem to be more prominent than in other patients with MPD1. Haplotype analysis suggests that the gene is located between polymorphic microsatellite markers D14S283 and D14S1034 on chromosome 14q11-q13. The presence of cardiomyopathy in some affected individuals may help in the identification of candidate genes.

Adult↗

Possible third case of Lin-Gettig syndrome.

We report a patient with craniosynostosis, severe mental retardation, absence of the corpus callosum, camptodactyly, hypogonadism, and ventricular septal defect. We propose that he has Lin-Gettig syndrome and that he is the third reported patient with this entity. Our patient also had additional phenotypic features, including palatal cleft and absent rapid eye movement (REM) sleep that were not present in the two previously described patients with this syndrome. High-resolution karyotype and subtelomeric fluorescence in situ hybridization (FISH) for cryptic telomeric rearrangement were normal. The existence of an unrelated patient with Lin-Gettig syndrome supports that this is a separate and distinct clinical entity.

Abnormalities, Multiple↗

Novel mental retardation-epilepsy syndrome linked to Xp21.1-p11.4.

We evaluated a kindred with X-linked mental retardation and epilepsy. Seven affected males with mild to moderate mental retardation developed seizures (primarily generalized, tonic-clonic, and atonic) that began on average at 6.8 months of age (range, 4 to 14 months). These patients did not have a history of infantile spasms. There were no dysmorphic features. Other than mental retardation, the neurological examination was unremarkable, with exception of 2 affected subjects who had mild generalized rigidity and ataxia. We identified tight linkage to a group of markers on Xp21.1-p11.4. A maximum two-point LOD score of +3.83 at straight theta = 0 was obtained for markers DXS8090, DXS1069, DXS8102, and DXS8085. This locus spans 7.7cM between DXS1049 and DXS8054 and does not overlap the locus for X-linked West syndrome. The tetraspanin gene, implicated in nonspecific mental retardation, is mapped to this region. We sequenced the tetraspanin coding sequence in subjects with X-linked mental retardation and epilepsy and did not identify disease-specific mutations. The syndrome we describe, designated X-linked mental retardation and epilepsy, is clinically and genetically distinct from X-linked West syndrome and other X-linked mental retardation-epilepsy syndromes.

Adolescent↗

Inherited dementias.

Dementia, defined as progressive cognitive decline, is a feature of a wide variety of genetic disorders. For example, a search of "dementia" in the Online Mendelian Inheritance in Man (www.ncbi.nlm.nih.gov/Omim) reveals 162 entries. Therefore this article cannot be encyclopedic and will be necessarily restricted to more prevalent or illustrative etiologies of familial dementia in adults. These disorders also have in common an initial and primarily dementing clinical presentation. Thus, this article is limited to: familial Alzheimer's disease (AD) and related amyloid angiopathies, frontotemporal dementias (FTD) and related tauopathies, familial prion diseases, British and Danish familial dementias, and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL).

Alzheimer Disease↗