title: Prenatal detection of del(10)(q11.2) mosaicism in chorionic villus specimens likely caused by a common chromosomal fragile site FRA10G is associated with a normal phenotype.
abstract: OBJECTIVE
  To summarize the pregnancy outcomes of cases with mosaicism for chromosome 10q11.2 deletion detected by chorionic villus sampling (CVS) and determine whether extensive cytogenetic work-up and follow-up amniocentesis are necessary in such cases.
  
  
  METHODS
  CVS was performed at 10-12 weeks of gestation. Chromosome analysis of chorionic villi was performed by standard G-banding techniques.
  
  
  RESULTS
  Mosaicism of chromosome 10q11.2 deletion was observed in 24 out of 6063 CVS cases (0.39%). A common fragile site, FRA10G is located at the breakpoint region. The level of mosaicism ranged from 4% to 25%. No evidence of mosaic 10q11.2 deletion was found in follow-up amniocentesis, maternal peripheral blood cells, or from cytogenetic studies of other pregnancies from the same group of patients. All these cases resulted in the live birth of normal healthy infants.
  
  
  CONCLUSIONS
  The presence of del(10)(q11.2) mosaicism in chorionic villus specimens most likely represents an in vitro culture artifact due to FRA10G fragile site in this region without any clinical consequences. If ultrasound results are normal, it is not necessary to perform follow-up amniocenteses and additional laboratory work-up for such cases.
authors.affiliation: Pittsburgh Cytogenetics Laboratory, Magee-Womens Hospital of UPMC, Pittsburgh, PA, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Liao
authors.forename: Malini
authors.initials: M
authors.lastname: Sathanoori
authors.forename: Svetlana A
authors.initials: SA
authors.lastname: Yatsenko
authors.forename: Jie
authors.initials: J
authors.lastname: Hu
authors.forename: Sally J
authors.initials: SJ
authors.lastname: Kochmar
authors.forename: Lori
authors.initials: L
authors.lastname: Hoffner
authors.forename: W Allen
authors.initials: WA
authors.lastname: Hogge
authors.forename: Urvashi
authors.initials: U
authors.lastname: Surti
mesh_terms: D002478:Cells, Cultured; D015193:Chorionic Villi Sampling; D002872:Chromosome Deletion; D025063:Chromosome Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology / Q000235:genetics; D043283:Chromosome Fragile Sites / Q000235:genetics* / Q000502:physiology; D002879:Chromosomes, Human, Pair 10; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007621:Karyotyping; D008297:Male; D009030:Mosaicism; D010641:Phenotype; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology; D011261:Pregnancy Trimester, First / Q000235:genetics / Q000502:physiology; D011296:Prenatal Diagnosis / Q000379:methods; D015995:Prevalence