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L Zelante

Publications and source records attributed to L Zelante.

137 records · Page 8Linked to original sources
PubMed1985

Frequency of consanguineous marriages among parents and grandparents of Down patients.

The existence of a rare autosomal gene which in the homozygous state would cause mitotic nondisjunction in the Down zygote has been hypothesized in the past by Alfi et al. (1980). This hypothesis can be supported or contradicted by the study of the frequency of consanguineous marriages among parents of affected children. Our study on 242 children affected with Down syndrome does not show any increase in the frequency of consanguineous marriages among their parents with respect to the general population, and therefore does not support the hypothesis of an autosomal gene controlling mitotic nondisjunction. Our data do not show any increase in the frequency of consanguineous marriages even among paternal and maternal grandparents of the affected children, thus not supporting the other possible explanation of an autosomal recessive condition in one of the patient's parents which would cause meiotic nondisjunction.

Adolescent↗
PubMedDate not supplied

Prenatal diagnosis of recurrence of cystic hygroma with normal chromosomes.

Cyst-like masses in the neck and back region, simulating an encephalocele, were detected by midtrimester ultrasound examinations in two sib fetuses. After termination, the fetuses were found to have large cystic hygromas. The present observation strongly suggests the existence of an autosomal recessive type of cystic hygroma.

Adult↗
PubMedDate not supplied

Multiple intracranial aneurysms in a patient with Seckel syndrome.

A 17-year-old girl affected by Seckel syndrome and multiple intracranial aneurysms is reported. Cerebral hemorrhage was the reason for the diagnostic work-up. The aneurysms were surgically treated. The main features of the syndrome, technical problems encountered during surgery and the prognosis of this condition are discussed.

Abnormalities, Multiple↗
PubMedDate not supplied

A complex mosaicism 45,X/46,X,del(Xq)/46,X,idic(Xq) in a patient with secondary amenorrhea.

A complex mosaicism involving the X chromosome was found in a 35-year-old female affected by secondary amenorrhea and short stature. Her karyotype was: 45,X[20]/46,X,del(X)(pter-->q26::qter)[15]/46,X,idic(X)(pter-->q26::q26-->pter)[9]. No cell contained both abnormal X chromosomes. This observation would suggest a possible mechanism underlying the formation of isodicentric chromosomes.

Adolescent↗
PubMedDate not supplied

Interstitial "de novo" tandem duplication of 7(q31.1-q35): first reported case.

A patient carrying a de novo 7q31-35 duplication is presented. The tandem duplication was confirmed by FISH analysis. The case seems to be the first in the literature and, in spite of the large size of the duplicated region, he shows mild facial dysmorphism and a moderate mental retardation. The clinical findings of the dup7q published cases are compared in order to define a possible common phenotype.

Chromosome Aberrations↗
PubMedDate not supplied

Two 48,XXYY patients: clinical, cytogenetic and molecular aspects.

Two 48,XXYY males, a young and an adult patient, have been clinically and molecularly analysed. Clinical findings seem less severe in the young patient. This clinical difference could be mainly due to the age of the younger patient or, alternatively, the different pattern of X-inactivation observed in the two patients could play a role in the degree of the clinical manifestations.

Adult↗
PubMedDate not supplied

Linkage analysis in two large Italian pedigrees affected with nail patella syndrome.

Nail patella syndrome (NPS) or osteo-onychodysplasia, is an autosomal dominant disorder characterised by nail dysplasia, absent or hypoplastic patellae, iliac horns and nephropathy. Previous studies have demonstrated linkage of the nail patella locus to the ABO and adenylate kinase loci on human chromosome 9q34. Recently, informative recombination events placed the NPS locus within a 1-2 cM interval within D9S60 and the AK1 gene. We describe here linkage analysis performed in two large Italian pedigrees with 10 and 11 members affected, respectively. A set of highly informative markers have been analysed and the allele segregation in the two families confirmed the linkage to chromosome 9. The presence of three recombination events allows definition of the critical region with a centrometric boundary between markers D9S1881 and D9S1840 and a telomeric boundary between markers D9S315 and D9S290.

ABO Blood-Group System↗
PubMedDate not supplied

[Current advances in the cytogenetics and molecular biology of the diagnosis of malformation syndromes].

Consistent progress has been obtained in recent years in the diagnosis and understanding of genetic disease. High resolution chromosome analysis has narrowed the gap between cytogenetics and Mendelism by proving that some diseases considered to be due to monogenic inheritance result in fact from deletion of contiguous genes or breakage of a specific gene. Gene "imprinting" has been found to be the cause of some syndromes, such as the Prader-Willi, Angelman, and Beckwith-Wiedemann. Molecular cytogenetics has become a tool for analysing small rearrangements not easily seen using traditional chromosome analysis, for detecting mosaicisms, and narrowing the "critical" regions of chromosomal syndromes. "Positional cloning" techniques have improved our ability to map disease-genes. Linkage studies and direct analysis of cloned genes are now having a large impact on the analysis of genetic diseases segregating in families, and in testing for healthy heterozygotes and presymptomatic patients. Discovery of mutations in the mitochondrial genome has widened our understanding of disease inheritance. A few disorders have been shown to be due to tandem amplification of GC-rich intragenic triplets. Genetic counseling has taken advantage of these improvements which have a large impact on our knowledge of genetic heterogeneity and variability.

Chromosome Aberrations↗
PubMedDate not supplied

Linkage of DFNB1 to non-syndromic neurosensory autosomal-recessive deafness in Mediterranean families.

Recent studies show a susceptibility locus (DFNB1) responsible for non-syndromic neurosensory autosomal-recessive deafness (NSRD) mapping to the pericentromeric region of chromosome 13q. In order to better understand the frequency with which DFNB1 is the gene for deafness in our patient population and the role of DFNB1 in Caucasians, we performed a genetic linkage study with four microsatellite markers linked to DFNB1 in a total of 48 independent Mediterranean families, of which 30 and 18 were of Italian and Spanish descent, respectively. A maximum two-point lod score of 7.28 was found with marker D13S115 at a recombination frequency of theta 0.1. Significant lod scores were also obtained for D13S143, D13S292 and D13S175. Genetic heterogeneity was confirmed using the HOMOG program which indicated absence of linkage to DFNB1 in approximately 21% of the sample. This study clearly demonstrates that DFNB1 plays an important role in 79% of Mediterranean families with NSRD. Furthermore, results from multipoint analysis predict that the DFNB1 gene maps between markers D13S175 and D13S115 which are separated by approximately 14.2 cM.

Chromosome Mapping↗
PubMedDate not supplied

A YAC contig spanning the blepharophimosis-ptosis-epicanthus inversus syndrome and propionic acidemia loci.

Blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) is an autosomal dominant condition consisting of congenital dysplasia of the eyelids with a reduced horizontal diameter of the palpebral fissures, droopy eyelids and epicanthus inversus. Two clinical entities have been described: type I and type II. The former is distinguished by female infertility, whereas the latter presents without other symptoms. Both type I and type II were recently mapped on the long arm of chromosome 3 (3q22-q23), suggesting a common gene may be affected. The centromeric and the telomeric limits of this region are well defined between loci D3S1316 and D3S1615, which reside approximately 5 cM apart. Here, we present the construction of a YAC contig spanning the entire BPES locus using 17 polymorphic markers, 2 STS and 28 ESTs. This region of approximately 5 Mb was covered by 31 YACs, and was supported by detailed FISH analysis. In addition, we have precisely mapped the propionyl-CoA carboxylase beta polypeptide (PCCB), the gene mutated in propionic acidemia, within this contig. Apart from providing a framework for the identification of the BPES gene, this contig will also be useful for the future identification of defects and genes mapped to this region, and for developing template resources for genomic sequencing.

Amino Acid Metabolism, Inborn Errors↗