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G A Danieli

Publications and source records attributed to G A Danieli.

At least 73 records · Page 4Linked to original sources
PubMed1994

The gene for arrhythmogenic right ventricular cardiomyopathy maps to chromosome 14q23-q24.

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVD) is a dominantly inherited disorder progressively affecting the myocardium and it is one of the major causes of juvenile sudden death. The chromosomal localization of the disease gene is reported here for the first time. A maximum lod score of 6.04 was obtained at theta = 0 for linkage with the polymorphic marker D14S42 (14q23-q24) in two families, one of which has 82 subjects (19 affected) in four generations. The pre-symptomatic identification of ARVD carriers by linkage analysis in the affected families strongly increases the possibility of prevention of life-threatening complications.

Arrhythmias, Cardiac↗
PubMed1994

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↗
PubMed1994

A report on 528 intragenic deletions detected in DMD and BMD patients by an Italian collaborative study.

The results of a collaborative study involving about one third of the total DMD and BMD cases living in the Italian territory are reported. The analysis of the breakpoint frequency by intron revealed significant differences among regional groups of DMD patients (for introns 2, 11 and 50 in Sardinia and for introns 9 and 45 in northeastern Italy), whereas no regional differences were observed among regional groups of BMD patients. These differences involve the same Italian regions which previous studies, performed by different markers, identified as "genetically differentiated". The data support the possibility of a differential distribution among populations of some intronic sequences, facilitating the origin of deletion breakpoints within the dystrophin gene.

Dystrophin↗
PubMed1993

(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↗
PubMed1993

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↗
PubMed1993

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↗
PubMed1993

Dystrophin-positive myotubes in innervated muscle cultures from Duchenne and Becker muscular dystrophy patients.

Nerve-muscle co-cultures from five Duchenne muscular dystrophy (DMD) patients and one Becker (BMD) patient, were studied by immunocytochemistry with antibodies against different portions of dystrophin. Four DMD patients had a deletion in the dystrophin gene. Some dystrophin-positive myotubes were detected in a few samples of all DMD cases. PCR amplification of exon 8 of the dystrophin gene ruled out a contamination from rat spinal cord during innervation. Our results in three DMD cases, may be explained by a clonal selection of dystrophin-positive fibers observed in muscle biopsies, while in the other two cases, a "frame-restoring" mutation might account for the presence of dystrophin-positive myotubes. The possible expression of "dystrophin-related protein" or dystrophin immature isoform was considered. In the BMD case an abnormal truncated dystrophin was found in innervated muscle cultures, as well as in muscle biopsy.

Adolescent↗
PubMed1993

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↗
PubMed1992

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↗
PubMed1992

Prevalence of dystrophin-positive fibers in 85 Duchenne muscular dystrophy patients.

The prevalence of dystrophin-positive fibers in Duchenne muscular dystrophy (DMD) muscle was estimated by direct counting on immunostained sections in a series of biopsy specimens from 85 patients, 42 of which were also screened for intragenic deletions by cDNA probes. Dystrophin-positive fibres are normotrophic and occur in muscle sections at a frequency between 0.01 and 6.81%. Frequencies over 1% were found only in patients older than 6 yr. The prevalence of dystrophin-positive fibers is about the same in patients with detectable and with undetectable deletions. The occurrence of positive fibers in small clusters supports the hypothesis of their clonal origin, suggesting that they may result from genetic reversion. No clinical differences were noticed in DMD patients of similar age with respect to the occurrence of dystrophin-positive fibres in their muscle biopsies.

Aging↗
PubMed1992

Screening for mutations in the muscle promoter region and for exonic deletions in a series of 115 DMD and BMD patients.

Mutations in the muscle promoter region and exonic deletions were screened in a series of 115 unrelated DMD and BMD patients from north-east Italy. No gross mutations of the promoter region were found. In three cases in which dystrophin of normal size was expressed at low levels, the analysis of DNA sequences of the promoter region failed to detect abnormalities. The majority of deletions in coding sequences, detected by cDNA probes, occur in the deletion hot spot identified by the probe P20. Intrafamilial variability in the severity of the disease is reported and discussed.

Adolescent↗
PubMed1992

Epidemiology of spinal muscular atrophies in a sample of the Italian population.

In the course of an epidemiological survey in four provinces of Veneto (northeastern Italy) 67 spinal muscular atrophy (SMA) cases (types I, II and III) were recorded. The survey spanned the period 1960-1983 and involved 859,891 consecutive live-born infants in a population of 2,635,800 inhabitants. The overall prevalence at birth for SMA types I, II and III was 7.8/100,000 live births. Type I alone accounted for 4.1/100,000 live births. If the hypothesis that SMA types I, II and III are clinical manifestations of allelic mutations is assumed, the mutation rate would be about 70 x 10(-6) and the frequency of the heterozygotes 1 in 57.

Female↗
PubMed1991

Genetic epidemiology of hereditary motor sensory neuropathies (type I).

Patients affected with hereditary motor sensory neuropathy (HMNS) type I were traced through hospital records. Each case was re-examined, a family history was drawn, and EMG examination was performed in those members of the family who could have inherited the trait. In the prevalence year 1987, in a population of 1,067,130 inhabitants of 2 contiguous provinces of northeast Italy, 100 living cases were recorded in 30 families, giving a minimal prevalence rate estimate of 9.37/100,000. HMSN I is inherited as an autosomal dominant trait, when clinical evaluation includes EMG. No difference may be established clinically between the 2 subtypes (Ia, linked to chromosome 1 and Ib, linked to chromosome 17). Sporadic cases are very rare and the mutation rate, including both the subtypes, is estimated between 3 and 6 X 10(-6).

Charcot-Marie-Tooth Disease↗
PubMed1991

X-linked Charcot-Marie-Tooth disease. A linkage study in a large family by using 12 probes of the pericentromeric region.

Linkage analysis was performed on 41 subjects belonging to a large family with a recurrence of X-linked Charcot-Marie-Tooth disease (CMTX), by using 12 restriction fragment length polymorphism markers mapping in p11-q13. The results are in agreement with previous linkage data. Three new markers that are potentially useful for genetic analysis of CMTX families are described. A more precise estimate of the localization of the disease locus was attempted by multipoint linkage analysis.

Blotting, Southern↗