title: [Carrier detection of Duchenne/Becker muscular dystrophy by analysis of STRs loci linked to the gene of dystrophin in Venezuelan families].
abstract: The Duchenne/Becker Muscular Dystrophy (DMD/BMD) is an X linked recessive lethal disease. The female carrier will transmit the disease gene to half of her sons and half of her daughters; half of the daughters will be carriers, while half will be normal. Half of the sons will be normal and, on average, half will have the disease. It is of particular relevance to be able to detect carrier status among female relatives of the patients for genetic counseling and prenatal diagnosis. The method of Short Tandem Repeat (STR) sequence polymorphism analysis can determine haplotype at normal status or at risk status and, to establish genetic linkage between the mutated gene and the segregated haplotype. We have analyzed 105 members from 15 unrelated Venezuelan families with one or more siblings affected with DMD/DMB and 7 unrelated males. Of the 105, 37 were male (26 affected and 11 normal) and 68 were female. STR sequences (STR44, STR45, STR49, STR50, STR3'DYS) of the gene of the Dystrophin were amplified by polymerase chain reaction (PCR) to analyze allelic polymorphism in the families. Five of the 15 families (33%) had a deletion of one or several of the exons. Of the 68 females, 27 (39.7%) were carriers, 27 (39.7%) were non-carriers and in 14 cases (20.58%) it was not possible to reach a definitive diagnosis. The definitive diagnosis could be established in 79% of the females. This analysis also shows that the mutation occurred on the grandpaternal X chromosome in one family. Hemizygocity was detected and carrier status ascertained in the mother of other patient and in one family we were able to do prenatal diagnosis. The germinal mosaicism could not be excluded in 3 patients.
authors.affiliation: Unidad de Genética Médica, Universidad del Zulia, Maracaibo, Venezuela.
authors.forename: Wilmer Noé
authors.initials: WN
authors.lastname: Delgado-Luengo
authors.forename: Lisbeth
authors.initials: L
authors.lastname: Borjas-Fuentes
authors.forename: William
authors.initials: W
authors.lastname: Zabala-Fernández
authors.forename: Erika
authors.initials: E
authors.lastname: Fernández-Salgado
authors.forename: Ernesto
authors.initials: E
authors.lastname: Solís-Añez
authors.forename: Carlos
authors.initials: C
authors.lastname: Chávez
authors.forename: Caridad
authors.initials: C
authors.lastname: Martínez-Basalo
authors.forename: Sandra
authors.initials: S
authors.lastname: González-Ferrer
authors.forename: Alicia
authors.initials: A
authors.lastname: Rojas-Atencio
authors.forename: Alisandra
authors.initials: A
authors.lastname: Morales-Machin
authors.forename: Joaquín
authors.initials: J
authors.lastname: Peña
authors.forename: Lennie
authors.initials: L
authors.lastname: Pineda-Bernal
authors.forename: Richard
authors.initials: R
authors.lastname: González
authors.forename: Luis Eduardo
authors.initials: LE
authors.lastname: Miranda
authors.forename: Juana
authors.initials: J
authors.lastname: Delgado-Luengo
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Hernández
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Chacín
authors.forename: Maribel
authors.initials: M
authors.lastname: Quintero
mesh_terms: D016189:Dystrophin / Q000235:genetics*; D005260:Female; D006579:Heterozygote; D006801:Humans; D008297:Male; D020388:Muscular Dystrophy, Duchenne / Q000235:genetics*; D010375:Pedigree; D020080:Tandem Repeat Sequences; D014687:Venezuela
chemical_list: D016189:Dystrophin