Molecular cytogenetic characterization of a patient diagnosed with dimorphic anemia carrying de novo rare ring chromosome 7 along with t(7;9). Poster presentation in ASHG 2014, San Diego, CA, October 18-22.
Cytogenetic abnormalities are described in a few patients with typical dimorphic anemia (DA). The possible clonal nature of this disease is still controversial. We present a case of a derivative chromosome 7 formed by a ring chromosome 7 and t(7;9). The patient is phenotypically normal. This is a unique case report from India, on occurrence of r(7) along with t(7;9). Patient is born to cytogenetically normal parents. We have performed conventional cytogenetic technique using GTG banding and molecular FISH technique using LSI D7S486 probe and WCP for chromosome 7 and 9. However, both the clinical features and the extent of cytogenetic imbalance of chromosome 7 and 9 are variable, and few reported cases of r(7) have been studied by molecular techniques. To our knowledge, this is the first report of r(7) and t(7;9) found in a child with dimorphic anemia, characterized by molecular cytogenetic analysis.