Duplication 2p and monosomy 8p in mosaicism: clinical, molecular cytogenetic and molecular markers of a unique case.
We report on a female patient, with a de novo mosaicism for a structural rearrangement producing trisomy 2p21-->pter and monosomy 8p21-pter. GTG bands and fluorescence in situ hybridization (FISH) in lymphocytes identified: mos 46,XX,der(8)(8qter-->8p21::p21::2p21-->pter),9qh +[52]/ 46,XX,9qh+[82]. Fibroblasts showed the same cell lines in 15 and 12 cells respectively. DNA profiling with fourteen autosomal STR markers, did not reveal a chimerism status in our patient. She did not present the classical phenotype described for trisomy 2p and for monosomy 8p probably due to approximately 60% of the patient's cells being normal. The abnormality probably arose in a very early stage of development during the first post-fertilization divisions with a non-sister chromatid exchange event between chromosomes 2 and 8 producing three cellular clones: a normal clone, one with trisomy 2p and monosomy 8p and a third with monosomy 2p and trisomy 8p. Only the first two cell lines were found in both lymphocytes and fibroblasts of hypopigmented skin; the third may have been lost or limited to other tissues.
Martínez
Angélica
A
Departamento de Genética, Instituto Nacional de Pediatría.
Ramos
Sandra
S
González-del Angel
Ariadna
A
Alcántara
Miguel Angel
MA
Molina
Bertha
B
Carnevale
Alessandra
A
D000015:Abnormalities, Multiple / Q000235:genetics*; D002675:Child, Preschool; D025063:Chromosome Disorders / Q000235:genetics* / Q000473:pathology; D020223:Chromosome Painting; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics*; D002898:Chromosomes, Human, Pair 8 / Q000235:genetics*; D003337:Corpus Callosum / Q000473:pathology; D004847:Epithelial Cells / Q000648:ultrastructure; D005260:Female; D005347:Fibroblasts / Q000648:ultrastructure; D006801:Humans; D007962:Leukocytes / Q000648:ultrastructure; D009006:Monosomy; D009030:Mosaicism; D011596:Psychomotor Disorders / Q000235:genetics* / Q000473:pathology; D014314:Trisomy