Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “TOOTH DISEASES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,081 records · Page 60Linked to original sources

Localization of mariner DNA transposons in the human genome by PRINS.

Homologous recombination occurring among misaligned repeated sequences is a significant source of the molecular rearrangements resulting in human genetic disease. Studies of the Charcot-Marie-Tooth disease locus on chromosome 17 have implicated the involvement of an ancient DNA transposon of the mariner family (Hsmar2) in the initiation of double-strand break events leading to homologous recombination. In this study, the genomic locations of 109 Hsmar2 elements were determined by primed in situ labeling (PRINS) using primers designed to match the right and left inverted terminal repeats (ITRs) of the transposon. Although the resolution of the PRINS technique is approximately 400 chromosomal Giemsa bands, the data presented here provide the first large-scale mapping study of these elements, which may be involved in initiation of homologous recombination events in the human genome.

Chromosome Mapping↗

Pigment variant of neuronal ceroid-lipofuscinosis.

A 6-year-old girl had progressive ataxia, and visual disturbances resulting in blindness. She died in her sleep at age 22 years. She shared with her sister and paternal relatives bilateral pes cavus deformities and impaired deep-tendon reflexes which suggested Charcot-Marie-Tooth disease. Her sister, who also had both polyneuropathy and a progressive central nervous system (CNS) disease, did not have pigmentary retinopathy. At autopsy, the patient was found to have neuronal ceroid-lipofuscinosis (NCL) marked by intraneuronal accumulation of autofluorescent granular lipopigments in ballooned perikarya and conspicuous extraneuronal pigmentation of subcortical grey matter, but without axonal spheroids. These findings indicate a pigment variant of NCL and represent one of very few patients recorded. The ultrastructure of the intraneuronal pigments was uniformly granular, while that of the extraneuronal pigments found within processes of the neuropil and glial perikarya was more variegated. In addition to those patients with the pigment variant of NCL, described earlier by Jakob and Kolkmann [1973: Acta Neuropathol (Berl) 26:225-236], and Jervis and Pullarkat [1978: Neurology 28:500-503], our patient shared clinical symptoms with those described in a family afflicted with polyneuropathy and NCL by Wisniewski et al. [1987: J Child Neurol 2:33-41]. Currently, it is unclear whether they have similar atypical forms of juvenile NCL (JNCL). We conclude that the spectrum of pigment variants in lysosomal diseases is heterogeneous: only few and recently described patients have had NCL, while others most likely had other forms of lipidosis.

Cerebral Cortex↗

Genetic refinement and physical mapping of the CMT4B gene on chromosome 11q22.

Charcot-Marie-Tooth disease type 4B (CMT4B) is a demyelinating autosomal recessive motor and sensory neuropathy characterized by focally folded myelin sheaths in the peripheral nerve. We recently mapped the CMT4B gene to a 5-cM interval on chromosome 11q22, using homozygosity mapping and haplotype sharing analysis on a large inbred pedigree. In the present study, we report the construction of a YAC-based transcript map across the 5-cM critical region, including 26 YACs, 35 STSs, and 52 ESTs. Furthermore, using 15 additional physically ordered microsatellite markers from the 11q22 region on the original inbred family, we were able to narrow the critical interval for the gene to 2 Mb, which is now flanked by markers D11S1757 and CHLC-GATA3B05. Finally, after computer analysis of the 33 ESTs assigned to the 2-Mb interval, we demonstrated that 21 different transcripts as well as 3 known genes might represent potential candidates for the disease.

Charcot-Marie-Tooth Disease↗

MR imaging in hypertrophic neuropathy: a case of hereditary motor and sensory neuropathy, type I (Charcot-Marie-Tooth).

We describe findings of Charcot-Marie-Tooth disease in magnetic resonance imaging (MRI). The MRI examination of the lumbar spine with and without gadolinium DTPA showed diffusely enlarged cauda equina, nerve roots, and ganglia. In the setting of appropriate family history and clinical presentation, the findings of diffusely enlarged nerve roots support the diagnosis of hereditary motor and sensory neuropathy, Type I (HMSN I, Charcot-Marie-Tooth).

Adult↗

Duplication in chromosome 17p11.2 in Charcot-Marie-Tooth neuropathy type 1a (CMT 1a). The HMSN Collaborative Research Group.

Hereditary motor and sensory neuropathy type I (HMSN I) or Charcot-Marie-Tooth disease type 1 (CMT 1) is an autosomal dominant disorder of the peripheral nervous system characterized by progressive weakness and atrophy of distal limb muscles. In the majority of HMSN I families, linkage studies localized the gene (CMT 1a) to the pericentromeric region of chromosome 17. We have detected with probe pVAW409R3 (D17S122) localized in 17p11.2 a duplication, co-segregating with the disease in 12 HMSN I families. In these families the duplication was present in all 128 patients but absent in the 84 unaffected and 44 married-in individuals (lod score of 58.44 at zero recombination). Further, on one HMSN I family the disease newly appeared simultaneously with a de novo duplication originating from an unequal crossing-over event at meiosis. Since different allelic combinations were found segregating with the duplication in different families linkage disequilibrium was not a significant factor. These findings led us to propose that the duplication in 17p11.2 itself is the disease causing mutation in all the HMSN I families analyzed.

Autoradiography↗

Absence of linkage with the Duffy blood group in a family with Charcot-Marie-Tooth neuropathy.

We report a large Belgian family with Charcot-Marie-Tooth disease (CMT) or hereditary motor and sensory neuropathy type I (HMSN-I). The pedigree consists of 5 generations with 350 family members comprising 42 patients. The disease is transmitted according to an autosomal dominant inheritance pattern. Several HMSN-I families have been reported to be closely linked to the Duffy blood group marker on chromosome 1. These families were designated HMSN-Ib families, opposed to the HMSN-Ia families which do not show evidence for such a linkage. Therefore we examined our family for the Duffy linkage relationship. We found no evidence for a strong linkage of the disease to the Duffy blood group locus, indicating that this family is of genetic subtype Ia.

Blood Group Antigens↗

Tomaculous neuropathy in chromosome 1 Charcot-Marie-Tooth syndrome.

We performed morphological and immunohistochemical studies on sural nerve biopsies from two members of a Charcot-Marie-Tooth type 1B family, in which a mutation of the P0 gene on chromosome 1 had been found. Biopsies showed a tomaculous neuropathy with loss of myelinated fibers and frequent small onion bulbs. Immunofluorescence with antibodies to P0 showed this protein to be present in tomaculous and non-tomaculous areas of the myelin sheath. The severity of the myelin abnormalities suggests that in this family Charcot-Marie-Tooth disease may result from a generalized disturbance of Schwann cells as a result of an abnormal P0 protein.

Biopsy↗

Technical pitfalls encountered in PCR quantification using microsatellites.

Quantitative PCR has proved useful for different purposes, including the detection of particular genetic changes, such as deletions and duplications in several inherited disorders. Using patients with the known duplication mutation for Charcot-Marie-Tooth disease Type 1A as examples, the importance of selecting informative microsatellite loci and proper electrophoretic conditions so as to eliminate potential sources of error in quantitative PCR studies is discussed.

Alleles↗

[Chronic distal spinal amyotrophy or spinal forms of Charcot-Marie disease. A report on six sporadic adult cases (author's transl)].

Based on a personal series of 6 cases, and about 20 cases reported in the published literature, the authors describe the principal characteristics of chronic distal amyotrophy of spinal origin: early onset or in young adults, initial disorder in lower limbs, especially anterolateral region of the legs, with secondary lesions in small muscles of the hands, absence of sensory disturbance, usually very slow progression, electrophysiological appearance of chronic denervation with normal conduction velocities, and neurogenic muscle lesions with unaffected peripheral nerve. These forms can be compared to the "spinal" forms of Charcot-Marie-Tooth disease and appear to be degenerative in origin even though proof by autopsy is lacking. In spite of their common characteristics, however, their genetic heterogenicity has to be noted: sporadic cases are seen most frequently but some cases are related to recessive autosomic transmission and others to dominant autosomic transmission. From the clinical point of view, some cases are distinctive in that there is early or predominant atrophy in the lower limbs, while others have lesions in muscles of bulbar innervation, which is against their origin from spinal amyotrophy. Finally, electrical signs at a distance from the atrophied muscles suggest extension of the pathological process. In spite of these comments, the authors suggest that the clinical concept of the distal form of spinal amyotrophy should be retained together with the proximal and scapuloperoneal forms.

Adult↗

[Further remarks on histochemistry applied to myodiagnosis: findings of "type predominance" (author's transl)].

Data concerning muscular biopsies (histochemically examined) of three patients affected by Charcot-Marie-Tooth disease, neurogenic atrophy of spondilosic origin and benign congenital hypotonia, are described. The common finding was a histochemical appearence of "type predominance". This point and the possible "neurogenic" origin of benign congenital hypotonia, are discussed.

Adult↗

Autosomal dominant distal spinal muscular atrophy in four generations.

Distal spinal muscular atrophy is a rare lower motor neuron disorder that may be difficult to distinguish clinically from type II Charcot-Marie-Tooth disease. We report on clinical and pathologic findings in 13 members of a four-generation extended family with autosomal dominant distal spinal muscular atrophy. The patients developed a slowly progressive lower motor neuron disorder involving mainly the distal lower extremities; onset was from the second to fourth decades. Electromyography and muscle biopsy findings were indicative of motor denervation. Combined silver/cholinesterase/immunocytochemical staining of intramuscular nerve revealed abundant collateral axonal branching in mild disease but marked loss of terminal motor endplate innervation in the more severe state, suggesting decreased growth of motor axon collaterals with disease progression. Multipoint DNA linkage analysis showed that this family's disorder is not linked to the chromosome 5q11.2-13.3 spinal muscular atrophy locus.

Adolescent↗

[Roussy-Lévy syndrome with a duplication on peripheral myelin protein gene (PMP22)].

A 51-year-old woman with autosomal dominant inheritance presented with finger tremor, atrophy of the dorsal interosseous muscles, and pes cavus. No muscular atrophy was noted in either leg. The deep tendon reflexes were only present for the biceps muscle of the arm, although they were decreased. Progression was extremely slow. Biopsy of the sural nerve revealed onion bulbs. The patient was diagnosed as a case of Roussy-Lévy syndrome. Her father and son had same symptoms. Typical Charcot-Marie-Tooth disease type 1A (CMT 1A) was also detected in the same family. All 4 cases revealed duplication of the PMP22 gene. In view of the molecular genetic findings, her Roussy-Lévy syndrome was considered to resemble CMT 1A.

Charcot-Marie-Tooth Disease↗

Studies of cellular radiosensitivity in hereditary disorders of nervous system and muscle.

Skin fibroblasts from patients with familial dysautonomia, Duchenne muscular dystrophy and Charcot-Marie-Tooth disease show normal sensitivity to ionising radiation, as measured by post-irradiation clonal growth. Previous reports of cellular hypersensitivity to ionising radiation and other DNA-damaging agents in familial dysautonomia and Duchenne muscular dystrophy have not been confirmed.

Adolescent↗

Isolation of a new strain of cytomegalovirus from explanted normal skin.

Forty-three fibroblast cell line were initiated from normal skin biopsies. One cell line from a patient with Charcot--Marie--Tooth disease (CMT) spontaneously developed c.p.e. suggestive of cytomegalovirus (CMV). Characterization of the virus showed it to be a new strain of CMV and the results suggested that skin fibroblasts from CMT patients may carry latent CMV.

Cell Line↗

Correlation between denervation activity and compound muscle action potential amplitude in hereditary motor and sensory neuropathy I and II.

Studying the electrophysiological characteristics of the various types of Charcot-Marie-Tooth disease is important in the understanding of its pathophysiology. The purpose of this study was to identify the frequency of fibrillation potentials and positive sharp waves (FP/PWs) in HMSN I and II and, since they are indices of denervation, to elucidate whether they are correlated with the amplitude of compound muscle action potentials (CMAP). We reviewed the electrophysiological findings of 47 patients who have been studied in our hospital and found to suffer from Charcot-Marie-Tooth polyneuropathy. FP/PW were graded according to a 4-grade scale and the 38 m/sec criterion for motor conduction velocity (MCV) was used for distinction between HMSN I and II subgroups. Seventy percent of HMSN II patients and 81% of HMSN I patients showed fibrillation potentials in the upper or lower limbs. There was no difference in the frequency of FP/PW appearance between the two groups. In the HMSN II group the FP/PW grade correlated with CMAP amplitude in the upper limbs. In both groups there was no correlation between FP/PW grade and MCV. Our findings might indicate that in HMSN I there is a considerable axonal destruction that occurs concurrently with myelin loss.

Action Potentials↗

A novel kinesin-like protein, KIF1Bbeta3 is involved in the movement of lysosomes to the cell periphery in non-neuronal cells.

The kinesin superfamily protein, KIF1Bbeta, a splice variant of KIF1B, is involved in the transport of synaptic vesicles in neuronal cells, and is also expressed in various non-neuronal tissues. To elucidate the functions of KIF1Bbeta in non-neuronal cells, we analyzed the intracellular localization of KIF1Bbeta and characterized its isoform expression profile. In COS-7 cells, KIF1B colocalized with lysosomal markers and expression of a mutant form of KIF1Bbeta, lacking the motor domain, impaired the intracellular distribution of lysosomes. A novel isoform of the kinesin-like protein, KIF1Bbeta3, was identified in rat and simian kidney. It lacks the 5th exon of the KIF1Bbeta-specific tail region. Overexpression of KIF1Bbeta3 induced the translocation of lysosomes to the cell periphery. However, overexpression of KIF1Bbeta3-Q98L, which harbors a pathogenic mutation associated with a familial neuropathy, Charcot-Marie-Tooth disease type 2 A, resulted in the abnormal perinuclear clustering of lysosomes. These results indicate that KIF1Bbeta3 is involved in the translocation of lysosomes from perinuclear regions to the cell periphery.

Animals↗

Mutations in the peripheral myelin genes and associated genes in inherited peripheral neuropathies.

The peripheral myelin protein 22 gene (PMP22), the myelin protein zero gene (MPZ, P0), and the connexin 32 gene (Cx32, GJB1) code for membrane proteins expressed in Schwann cells of the peripheral nervous system (PNS). The early growth response 2 gene (EGR2) encodes a transcription factor that may control myelination in the PNS. Mutations in the respective genes, located on human chromosomes 17p11.2, 1q22-q23, Xq13.1, and 10q21.1-q22.1, are associated with several inherited peripheral neuropathies. To date, a genetic defect in one of these genes has been identified in over 1,000 unrelated patients manifesting a wide range of phenotypes, i.e., Charcot-Marie-Tooth disease type 1 (CMT1) and type 2 (CMT2), Dejerine-Sottas syndrome (DSS), hereditary neuropathy with liability to pressure palsies (HNPP), and congenital hypomyelination (CH). This large number of genetically defined patients provides an exceptional opportunity to examine the correlation between phenotype and genotype.

Charcot-Marie-Tooth Disease↗

A novel locus for autosomal recessive peripheral neuropathy in the EGR2 region on 10q23.

During our studies of Romany (Gypsy) families with hereditary motor and sensory neuropathy-Lom, we have identified a large kindred with two independently segregating autosomal recessive neuropathies. The novel disorder, named "hereditary motor and sensory neuropathy-Russe" (HMSNR), presented as a severe disabling form of Charcot-Marie-Tooth disease with prominent sensory loss, moderately reduced motor nerve conduction velocity, and a high threshold for electrical nerve stimulation. A genome scan in two branches of the large kindred detected linkage to the 10q22-q23 region containing the early growth response 2 gene (EGR2), a transcription factor with a key role in peripheral nerve myelination. The results of sequence analysis and the detection of an intragenic polymorphism allowed us to exclude EGR2 as the HMSNR gene. Further analysis done using linkage and recombination mapping refined the position of the HMSNR gene to a small interval on 10q23.2, flanked by markers D10S581 and D10S1742, telomeric to EGR2. In this interval, a conserved seven-marker haplotype is shared by all disease chromosomes, suggesting a single founder mutation. The homozygosity region is contained in bacterial-artificial-chromosome contig 1570 of the Sanger Centre physical map and has an estimated physical size of approximately 500 kb.

Charcot-Marie-Tooth Disease↗