PubMed Health⌕ Search

Biomedical subjects

M L Mostacciuolo

Publications and source records attributed to M L Mostacciuolo.

At least 37 records · Page 2Linked to original sources

Prediction of myotonic dystrophy clinical severity based on the number of intragenic [CTG]n trinucleotide repeats.

We carried out a genotype-phenotype correlation study, based on clinical findings in 465 patients with myotonic dystrophy (DM), in order to assess [CTG] repeat number as a predictive test of disease severity. Our analysis showed that the DM subtypes defined by strict clinical criteria fall into three different classes with a log-normal distribution. This distribution is useful in predicting the probability of specific DM phenotypes based on triplet [CTG] number. This study demonstrates that measurement of triplet expansions in patients' lymphocyte DNA is highly valuable and accurate for prognostic assessment.

Disease Progression↗

Genetic epidemiology of congenital muscular dystrophy in a sample from north-east Italy.

Congenital muscular dystrophy (CMD) is a heterogeneous disease with autosomic recessive transmission. In an epidemiological study in four provinces of Veneto (region of 2 586 830 inhabitants in north-east Italy), the recorded incidence rate for the period 1979-1993 was 4.65 x 10(-5); the prevalence rate in the year 1993 was 6.8x10(-6). The incidence and the prevalence rates that we have obtained during the course of our investigation represent the first estimates for CMD in Europe and show that this myopathy is among the most frequent neuromuscular diseases with autosomic recessive transmission.

Child↗

Discordant clinical outcome in type III spinal muscular atrophy sibships showing the same deletion pattern.

Three type III spinal muscular atrophy (SMA) families are described in which the same deletion pattern for SMN gene and flanking loci is apparent in both affected and unaffected siblings. Deletions extending to include the NAIP gene are reported in one sibship. All three individuals in which SMN and/or NAIP deletions were detected showed the same haplotypes for SMA linked microsatellite markers as their affected sibs. The three index cases had a SMA III with early onset (1.5-2 yr) and became chairbound at the age 4, 5 and 20 yr. The three haploidentical sibs were given a clinical severity score. One of them showed no sign of the disease at the age of 4 yr and was considered "unaffected"; a 35-yr-old female, who had no symptoms but showed tongue fasciculations and hand tremor was considered "asymptomatic"; a 34-yr-old female, who had mild muscular weakness since the age of 24, was rated "mild". These observations demonstrate the presence of a continuum of clinical variability within SMA III families. These data suggest that, in these three families at least, the SMA phenotype is caused or influenced by another gene(s) additional to SMN.

Adult↗

Estimation of the mutation frequencies in Charcot-Marie-Tooth disease type 1 and hereditary neuropathy with liability to pressure palsies: a European collaborative study.

A European collaboration on Charcot-Marie-Tooth type 1 (CMT1) disease and hereditary neuropathy with liability to pressure palsies (HNPP) was established to estimate the duplication and deletion frequency, respectively, on chromosome 17p11.2 and to make an inventory of mutations in the myelin genes, peripheral myelin protein 22 (PMP22), myelin protein zero (MPZ) and connexin 32 (Cx32) located on chromosomes 17p11.2, 1q21-q23 and Xq13.1, respectively. In 70.7% of 819 unrelated CMT1 patients, the 17p11.2 duplication was present. In 84.0% of 156 unrelated HNPP patients, the 17p11.2 deletion was present. In the nonduplicated CMT1 patients, several different mutations were identified in the myelin genes PMP22, MPZ and Cx32.

Charcot-Marie-Tooth Disease↗

Frequency of duplication at 17p11.2 in families of northeast Italy with Charcot-Marie-Tooth disease type 1.

Charcot-Marie-Tooth disease type 1 (CMT 1) is the most common form of the hereditary motor sensory neuropathies (HMSN) with a prevalence in the Italian population of 9.4/100,000 inhabitants. CMT 1 is a genetically heterogeneous disorder. Forty CMT 1 families (35 with recurrence of cases and 5 sporadic cases) living in northeastern Italy were analyzed with the probe pVAW409R3 to reveal the presence of 17p11.2 duplication. The duplication frequency that resulted was about 82% and not significantly different in familial and in sporadic cases (p = 0.801). This kind of molecular analysis can be very useful for the differential diagnosis of CMT 1 and for the early diagnosis in the absence of a clear clinical manifestation.

Alleles↗

Occurrence of two different intragenic deletions in two male relatives affected with Duchenne muscular dystrophy.

The occurrence of 2 different intragenic deletions (exons 10-44 and exon 45, respectively) is reported in 2 male relatives affected with Duchenne muscular dystrophy, both showing the same haplotype for DNA markers not included in the deleted segment. The 2 different deletions seem to have occurred independently in the same X chromosome. This finding, together with other reports, suggests possibly an increased predisposition to mutations within the DMD locus in some families. Therefore, when dealing with prenatal diagnosis, the investigation on fetal DNA cannot be restricted only to the region in which a mutation was previously identified in the family.

Child↗

A study on duplications of the dystrophin gene: evidence of a geographical difference in the distribution of breakpoints by intron.

Starting from a group of 265 Italian patients affected with Duchenne or Becker muscular dystrophy a screening for duplications in the dystrophin gene was performed on 112 cases in which no deletions had previously been detected. The 21 intragenic duplications detected account for 7.9% of the total. Among these, one duplication including exons from 3 to 43 is the largest reported so far. Data from this study were combined with those from the literature and breakpoint distribution by intron was analysed. In general breakpoints occur mostly in the proximal third of the gene, in particular in intron 7. However, both the frequency of duplications and the distribution of breakpoints by intron are different in the Japanese sample compared with the other groups of patients. The role of geographical differentiation of intron sequences by genetic drift and of transposon-like sequences in explaining these differences is discussed.

Canada↗

Mutations in the connexin 32 gene in X-linked dominant Charcot-Marie-Tooth disease (CMTX1)

X-linked dominant Charcot-Marie-Tooth disease (CMTX1) is a peripheral neuropathy which maps to Xq13 and is flanked by the loci DXS106 (Xq11.2-q12) and DXS559 (Xq13.1). Contained within this interval of approximately 2-3Mb of DNA is the gene, connexin 32 (locus designation GJ beta 1). This gene encodes a gap junction protein which is expressed in large quantities within the liver and throughout a range of other mammalian tissues. We have sequenced the coding region of exon 2 of this gene from affected individuals in nine families with CMTX 1 and have found mutations which segregate with the disease in eight of these families. The mutations detected include missense point mutations at codons 15, 60, 63, 208, and 215, a nonsense point mutation at codon 220, deletions of one base in codon 72/3 producing a stop codon 12 codons down stream and a three base pair deletion which can be predicted to result in the loss of a single amino acid. These findings are consistent with the disease CMTX1 being the result of mutations affecting the gene connexin 32 (Cx32).

Amino Acid Sequence↗

Non-radioactive detection of 17p11.2 duplication in CMT1A: a study of 78 patients.

Charcot-Marie-Tooth disease type 1 (CMT1) is a peripheral neuropathy characterised by progressive distal muscular atrophy and sensory loss with markedly decreased nerve conduction velocity, mostly inherited as an autosomal dominant trait. The most common form, type 1A, is associated with a 1.5Mb DNA duplication in region p11.2-p12 of chromosome 17 in many patients. In this study a non-radioactive test for detection of the CMT1A duplication based on an RM11-GT microsatellite polymorphism is presented. Although different methods have been devised for this purpose, the present method has the advantage of being rapid, informative, economical, easily interpretable, and, therefore, it represents a very useful tool for diagnosis of CMT1A, especially before clear manifestation of clinical symptoms. Seventy-eight patients diagnosed clinically as having CMT and evaluated by electrophysiological methods were tested with an RM11-GT microsatellite and with probe pVAW409R3. The CMT1A duplication was found in 76% of the 56 unrelated patients. RM11-GT was the most informative marker with a heterozygosity of 89%.

Base Sequence↗

X linked Charcot-Marie-Tooth disease (CMTX1): a study of 15 families with 12 highly informative polymorphisms.

X linked dominant Charcot-Marie-Tooth disease (CMTX1) has previously been localised to Xq13-21. Fifteen families were studied using 12 highly informative polymorphisms in the pericentric region of the X chromosome. Phase known recombinations in these families localise the X linked dominant CMT gene to the region distal to DXS106 (Xq11.2-12) and proximal to DXS559 (Xq13.1). These markers flank approximately 2 to 3 Mb of DNA to which GJB1 and CCG1 have already been mapped. A recent report of mutations in the GJB1 gene in subjects with CMTX1 makes this a strong candidate gene.

Cell Cycle↗

(CTG)n triplet mutation and phenotype manifestations in myotonic dystrophy patients.

A genotype-phenotype study based on the primary clinical features of adult myotonic dystrophy (DM) included 116 patients from 62 Italian pedigrees. A significant correlation between clinical severity and the number of repeats at the 3' untranslated region of the myotonin-protein kinase gene (MT-PK) was found. These results suggest that the CTG amplification is directly related to the myotonic dystrophy phenotype and provide important information on morbidity and prognosis in this disease.

Adolescent↗

Patterns of deletions of the dystrophin gene in different European populations.

The distribution of deletion breakpoints in the dystrophin gene was studied in a series of subjects belonging to different European populations. The data, obtained from the literature or directly from the present study, refer to population samples from France, Finland, Germany, Italy, Netherlands, Switzerland, and U.K. (England, Scotland, Wales). In total, 1516 breakpoints were assigned to different introns, 359 in the region encompassing the first 40 exons and 1157 (76%) in the distal part of the gene. Intron 7 appears to be equally involved as the starting or ending breakpoint, whereas intron 44 is involved mostly as a starting breakpoint. Breakpoint distribution by intron seems to differ in different populations, reaching statistical significance in the case of introns 44, 49, and 53. This finding suggests that some intronic sequences might contain preferential breakpoints that might vary in different populations, possibly as a consequence of genetic drift.

Chromosome Fragility↗

Cardiac involvement in Becker muscular dystrophy.

OBJECTIVES: The purpose of this study was to assess the incidence of myocardial involvement and the relation of cardiac disease to the molecular defect at the deoxyribonucleic acid (DNA) or protein level in Becker muscular dystrophy. BACKGROUND: Dystrophin gene mutations produce clinical manifestations of disease in the heart and skeletal muscle of patients with Becker muscular dystrophy. METHODS: Thirty-one patients underwent electrocardiographic and echocardiographic examination and 24-h Holter monitoring. The diagnosis was established by neurologic examination, dystrophin immunohistochemical assays or Western blot on muscle biopsy, or both, and DNA analysis. RESULTS: Electrocardiographic and echocardiographic findings were abnormal in 68% and 62% of the patients, respectively. Right ventricular involvement was detected in 52%. Left ventricular impairment was observed either as an isolated phenomenon (10%) or in association with right ventricular dysfunction (29%). Right ventricular disease was manifested in the teenagers, and an impairment of the left ventricle was observed in older patients. Right ventricular end-diastolic volumes were significantly increased compared with those in a control group. The left ventricular ejection fraction was significantly lower in older patients than in control subjects or younger patients. Life-threatening ventricular arrhythmias were detected in four patients. No correlations were found between skeletal muscle disease, cardiac involvement and dystrophin abnormalities. In our patients, exon 49 deletion was invariably associated with cardiac involvement. Exon 48 deletion was associated with cardiac disease in all but two patients. CONCLUSIONS: The cardiac manifestation of Becker muscular dystrophy is characterized by early right ventricular involvement associated or not with left ventricular impairment. Exon 49 deletion is associated with cardiac disease.

Adolescent↗

Reappraisal of the incidence rate of Duchenne and Becker muscular dystrophies on the basis of molecular diagnosis.

The incidence rates of Duchenne and Becker muscular dystrophies (X-linked recessive) in a given sample of the Italian population were recalculated using the results of DNA and dystrophin analysis. While the incidence rate of Duchenne muscular dystrophy remained unchanged, the new figure for the incidence of Becker muscular dystrophy (7.2 per 100,000 male live births) was much higher than previously reported, since molecular diagnosis revealed additional cryptic cases, but this incidence is still an underestimate.

Blotting, Western↗

Further evidence of a duplication in 17p11.2 in families with recurrence of HMSN Ia (Charcot-Marie-Tooth neuropathy type Ia).

Five Italian families with recurrence of cases of Charcot-Marie-Tooth disease (type Ia) were analysed using three closely linked DNA probes that detect polymorphisms in the region 17p11.2. The probe pVAW409R3 detected the presence of a duplication in all the affected subjects, but not in the subjects with normal electromyographic (EMG) findings. This observation confirms previous data indicating the association of the duplication with the disease, suggesting that, at least in populations of European origin, the duplication might be the molecular feature diagnostic of the pathological trait.

Charcot-Marie-Tooth Disease↗

Multipoint linkage mapping of the Emery-Dreifuss muscular dystrophy gene.

The clinical features to establish the diagnosis of X-linked Emery-Dreifuss muscular dystrophy (EMD) were recently redefined at the European EMD workshop in Baarn 1991. These criteria were used to select families from the literature and two new families for linkage analysis with the DNA markers F9, DX52, DXS15, F8C and DXS115. Recombinations are observed with the DNA markers F9, DXS52 and DXS15. No recombinations were found with F8C and DXS115. Multipoint linkage analysis indicates with a maximum location score of 73.9 that the EMD locus maps very close to F8C.

Adult↗