title: Clinical utility of chromosomal microarray analysis in the diagnosis and management of monosomy 7 mosaicism.
abstract: There have been dramatic improvements in our ability to more accurately diagnose the underlying genetic causes of developmental delay/intellectual disability; however, there is less known about the treatment trajectory and whether or not patient management and outcomes have changed due to the information gained from genetic testing. Here we report a case study of a 20-month-old male first referred to the genetics clinic in 2008 for interhemispheric cysts, agenesis of the corpus callosum, left cortical dysplasia, and developmental delay of unknown etiology. The diagnostic work-up for this patient included chromosomal microarray which detected >20% mosaicism for monosomy 7, which raised concern for a possible myelodysplastic syndrome. The clone was not detected in stimulated peripheral blood cultures and his karyotype was reported as a normal male. Because of this microarray finding, he was referred to pediatric hematology/oncology where he was confirmed to have a pre-symptomatic diagnosis of myelodysplastic syndrome and was treated with chemotherapy and a bone-marrow transplant. This case illustrates the clinical utility of microarray testing and the importance of long-term follow-up to assess patient outcomes.
authors.affiliation: Greenwood Genetic Center, Greenwood, SC USA.
authors.forename: Alka Chaubey Nee
authors.initials: AC
authors.lastname: Dwivedi
authors.affiliation: Greenwood Genetic Center, Greenwood, SC USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Lyons
authors.affiliation: Affymetrix, Inc, Santa Clara, CA USA.
authors.forename: Kat
authors.initials: K
authors.lastname: Kwiatkowski
authors.affiliation: Greenwood Genetic Center, Greenwood, SC USA.
authors.forename: Frank O
authors.initials: FO
authors.lastname: Bartel
authors.affiliation: Greenwood Genetic Center, Greenwood, SC USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Friez
authors.affiliation: Greenwood Genetic Center, Greenwood, SC USA.
authors.forename: Kenton R
authors.initials: KR
authors.lastname: Holden
authors.affiliation: Affymetrix, Inc, Santa Clara, CA USA.
authors.forename: Eric T
authors.initials: ET
authors.lastname: Fung
authors.affiliation: Greenwood Genetic Center, Greenwood, SC USA.
authors.forename: Barbara R
authors.initials: BR
authors.lastname: DuPont
keywords: Microarray; Monosomy 7; Mosaicism; Myelodysplasia