title: [Blood cell chimerism in dizygotic twins conceived by in vitro fertilization].
abstract: We present a case of hematopoietic chimerism in dizygotic twins (male and female) conceived by in vitro fertilization (IVF). At 8 years of age a blood karyotype was performed on the female due to the presence of clitoromegaly. Two different lines: 46,XX (53%) and 46,XY (47%) were found. FISH studies confirmed the presence of the SRY gene in 46,XY cells. Karyotyping of the male showed two different lines: 46,XY (58%) and 46,XX (42%). SRY gene was present in 46,XY cells. Microsatellite analyses of blood DNA revealed tetra-allelic contribution at some autosomal loci with similar proportions of maternal and paternal alleles and X/Y chromosome dose. FISH in buccal mucous showed that all cells from the female were 46,XX and those from the male 46,XY. The gonadal karyotype in the female was 46,XX without SRY. Hence, we report 46,XX/46,XY chimerism in dizygotic twins. Blood chimerism was confirmed by performing FISH on the buccal cells of the patients.
authors.affiliation: Servicios de Pediatría y Endocrinología, Instituto de Investigación La Princesa, Hospital Infantil Universitario Niño Jesús, Madrid, España; Departamento de Pediatría, Universidad Autónoma de Madrid, Madrid, España; Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Madrid, España.
authors.forename: G Á
authors.initials: GÁ
authors.lastname: Martos-Moreno
authors.forename: C
authors.initials: C
authors.lastname: Campos
authors.forename: R
authors.initials: R
authors.lastname: Flores
authors.forename: R
authors.initials: R
authors.lastname: Yturriaga
authors.forename: L A
authors.initials: LA
authors.lastname: Pérez-Jurado
authors.forename: J
authors.initials: J
authors.lastname: Argente
mesh_terms: D001773:Blood Cells; D002648:Child; D046528:Chimerism; D002987:Clitoris / Q000002:abnormalities; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007621:Karyotyping; D008297:Male; D010375:Pedigree; D010641:Phenotype; D014429:Twins, Dizygotic / Q000235:genetics*
keywords: Cariotipo; Chimerism; Dizygotic twins; Gemelos dicigotos; Karyotype; Quimerismo