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J F Mattei

Publications and source records attributed to J F Mattei.

At least 19 recordsLinked to original sources
PubMed1999

Characterization of a new polymorphism, IVS-I-108 (T-->C), and a new beta-thalassemia mutation, -27 (A-->T), discovered in the course of a prenatal diagnosis.

We report two new substitutions, IVS-I-108 (T-->C) and -27 (A-->T), identified in a couple at risk for beta-thalassemia. One is of Iranian origin and presents with two mutations: a new substitution of T-->C at nucleotide IVS-I-108, which is a silent polymorphism, and a previously described beta-thalassemia mutation at nucleotide -28 (A-->C). The other is from the island of Corsica, the only place in France where beta-thalassemia is endemic. He presents a new substitution of A-->T at nucleotide -27 in the TATA box, which was also found in several members of his family with the beta-thalassemia trait. The fetus was found to have inherited both these novel mutations.

Female↗
PubMed1999

Angelman syndrome resulting from UBE3A mutations in 14 patients from eight families: clinical manifestations and genetic counselling.

Angelman syndrome (AS) is a neurological disorder with a heterogeneous genetic aetiology. It most frequently results from a de novo interstitial deletion in the 15q11-q13 region, but in a few cases it is caused by paternal uniparental disomy (UPD) or an imprinting mutation. The remaining 20 to 30% of AS patients exhibit biparental inheritance and a normal pattern of allelic methylation in the 15q11-q13 region. In this latter group, mutations in the UBE3A gene have recently been shown to be a cause of AS. Here we describe the phenotypic expression in 14 AS cases involving eight UBE3A mutations. These comprise 11 familial cases from five families and three sporadic cases. Subtle differences from the typical phenotype of AS were found. Consistent manifestations were psychomotor delay, a happy disposition, a hyperexcitable personality, EEG abnormalities, and mental retardation with severe speech impairment. The other main manifestations of AS, ataxia, epilepsy, and microcephaly, were either milder or absent in various combinations among the patients. In addition, myoclonus of cortical origin was frequently observed with severe fits inducing myoclonic seizures. The majority of the patients were overweight. This study showed that ataxia, myoclonus, EEG abnormalities, speech impairment, characteristic behavioural phenotype, and abnormal head circumference are attributable to a deficiency in the maternally inherited UBE3A allele. Furthermore, analysis of mutation transmission showed an unexpectedly high rate of somatic mosaicism in normal carriers. These data have important consequences for genetic counselling.

Adolescent↗
PubMed1997

[Genetics and society: ethic and legal implications].

Medical genetics, recently individualised as a full medical specialty, evidences new problems issued from its natural and historical developments. Genetics counselling, prenatal and predictive diagnosis may be considered as a real progress when applied in the strictly medical and individual fields. When extended to the whole community to answer collective choices, these technologies can turn into eugenic and standardizing practices. Regarding the public health and the economic necessity it could be inviting to overpass the essential values on which are founded our humanity. In that context laws are required to defend the best use for human being several practices, but only after an ethical debate in which everyone should participate.

Ethics, Medical↗
PubMed1996

[Genetic hemoglobin diseases. Prevention at centers for family planning and education of maternal-child protection in Marseille].

OBJECTIVES: Diseases due to inherited hemoglobin disorders represent serious medical, social, and economic problems in the region of Marseille. The only effective treatment for such diseases is allogenic bone marrow transplantation. About 200 patients with either thalassemia, sickle cell or sickle cell-beta thalassemic diseases are regularly seen in local hospitals. All of these patients come from parts of the world where genetic hemoglobin disorders are endemic. METHODS: At this time, the only approach for reducing the number of affected children born is preventive. This depends upon education, the detection of carriers, genetic counselling and sometimes, prenatal diagnosis. We have organised a program of prevention supported by a grant from the DISS (Direction des Interventions Sociales et Sanitaires) in the context of visits made to the PMI (Prevention Maternelle et Infantile). This initiative concerns women presenting for consultations for three reasons: for a prenuptial check-up, for a pregnancy, and for prescription of contraceptives. RESULTS: In each of these three situations a check-up is obligatory and, for natives of countries where hemoglobin disorders are common, a hemoglobin test is recommended. If this test reveals an abnormality, the partner or husband is also tested, if he is willing. Couples who are both carriers are given genetic counselling. CONCLUSION: This preventive initiative has yielded valuable results so we hope to follow-up on the approach and extend it to other centers. Such screening, based upon the geographic origins of patients, can be implemented in the course of a consultation by any doctor.

Anemia, Sickle Cell↗
PubMed1996

Unexpected inheritance of the (CGG)n trinucleotide expansion in a fragile X syndrome family.

The fragile X syndrome is the most frequent cause of inherited mental retardation. CGG repeat alleles are usually classified as normal, premutation, or full mutation based on the length of this triplet in the 5' untranslated region of the FMR1 gene. The pattern of inheritance follows a two-stage intergenerational process in which the premutation evolves into the full mutation. Some reverse mutations have been described, but they appear to be very rare. We describe a family in which a mother of two affected males herself carried a full mutation. Surprisingly, her clinically normal daughter, initially considered to be a carrier by linkage analysis, carried a very short premutation. Findings from our family study corroborate the hypothesis that the expansion during female transmission could be a postzygotic event and raise the problem of mosaicism.

Blotting, Southern↗
PubMed1994

[Angelman syndrome].

The Angelman syndrome is a neurological disorder characterized by constant features: severe mental retardation, easily provoked laughter, ataxia, absent speech, seizures. Most cases are sporadic but familial cases have been reported. About 60 to 70% of cases are due to an interstitial deletion on the maternally inherited chromosome 15 in the region q11-q13. Rare cases result from paternal disomy. In 30% of patients, neither maternal by inherited deletion, nor paternal disomy, can be found. In this category of patients recurrence risk for sibs is high and molecular mechanisms are not completely known. They appear to be more complex than previously suggested. It is clear that this syndrome is a genetically heterogeneous group. The main example of genomic imprinting in human pathology, Angelman syndrome is now a model in research for understanding molecular mechanisms underlying imprinting.

Angelman Syndrome↗
PubMed1993

Physical mapping of microdeletions of the chromosome 17 short arm associated with Smith-Magenis syndrome.

We used probes from the juxta-centromeric region of the chromosome 17 short arm to map three microdeletions in patients with Smith-Magenis syndrome. The common clinical findings were: speech delay with behavioural problems associated with broad flat midface, brachycephaly, broad nasal bridge and brachydactyly. We demonstrated, using Southern blot analysis (loss of heterozygosity and gene dosage), that all patients were deleted for two p11.2 markers: pYNM 67-R5 (D17S29) and pA10-41 (D17S71). We determined that one breakpoint was located between D17S58 and D17S29 and the other breakpoint distal to D17S71. The possibility that an unstable region, located between the Smith-Magenis syndrome locus and CMT1A a closely located locus, could be involved in the rearrangements associated with these two inherited diseases is discussed.

Abnormalities, Multiple↗
PubMed1993

The Juberg-Marsidi syndrome maps to the proximal long arm of the X chromosome (Xq12-q21).

Juberg-Marsidi syndrome (McKusick 309590) is a rare X-linked recessive condition characterized by severe mental retardation, growth failure, sensorineural deafness, and microgenitalism. Here we report on the genetic mapping of the Juberg-Marsidi gene to the proximal long arm of the X chromosome (Xq12-q21) by linkage to probe pRX214H1 at the DXS441 locus (Z = 3.24 at theta = .00). Multipoint linkage analysis placed the Juberg-Marsidi gene within the interval defined by the DXS159 and the DXYS1X loci in the Xq12-q21 region. These data provide evidence for the genetic distinction between Juberg-Marsidi syndrome and several other X-linked mental retardation syndromes that have hypogonadism and hypogenitalism and that previously. Finally, the mapping of the Juberg-Marsidi gene is of potential interest for reliable genetic counseling of at-risk women.

Abnormalities, Multiple↗
PubMed1992

Prenatal diagnosis of Fryns' syndrome.

We report on a new case of ultrasonographic prenatal diagnosis of Fryns' syndrome during the second pregnancy of a young woman whose first child died 90 min after birth and was diagnosed as having this autosomal recessive condition. The feasibility of diagnosis in utero and timing in the phenotypic expression of this multimalformation syndrome are discussed.

Abnormalities, Multiple↗
PubMed1992

Physical mapping of an Xq-proximal interstitial duplication in a male.

A viable duplication in the proximal long arm of the X chromosome in a boy with a malformative syndrome was delineated with molecular biology techniques using 14 probes from the X cen-Xq21 region. This analysis allowed us to refine the physical map of the X cen-Xq13 region.

Abnormalities, Multiple↗
PubMed1992

[Vitamin D-resistant rickets type II: apropos of 2 cases].

We present two cases of vitamin D-dependent rickets type II, a rare disease caused by a hereditary disorder of the receptor for 1,25 dihydroxyvitamin D (1,25 (OH) 2 D). The first patient was seen for the first time at the age of 2 years with florid rickets, almost complete alopecia, and an elevated plasma level of 1,25 (OH) 2 D; there was no improvement following treatment with 1 alpha-hydroxy-vitamin D3). The second patient, a boy whose parents are first cousins, was seen at the age of 7 years with severe rickets, partial alopecia and an elevated serum level of 1,25 (OH) 2 D; the rickets disappeared after administering high doses of 1 alpha hydroxyvitamin D3 and vitamin D.

Alopecia↗