Cytogenetic characterization of an extra structurally abnormal

GORLA N, SLAVUTSKY I, LISANTI J, PEDRAZZINI E, VANELLA L, , LARRIPA I

HEREDITAS

WILEY-BLACKWELL PUBLISHING, INC

Año: 1998 vol. 129 p. 1 - 5

0018-0661

We have studied an extra structually abnormal chromosome (ESAC) in a 13 years old boy with profound mental, psychomotor and speech retardation, behavioral problems, seizures and abnormal electroencephalogram. The examina- tion of the bisatellited ESAC with chromosome banding demonstrated that the karyotype was: 47, XY, +inv dup (15) (pter + ql3::ql3 + pter). The cytogenetic characterization of the inv dup (1 5) is reported with special emphasis on the usefulness of DA/DAPI staining when G-banding is sequentially performed to discard possible heteromorphisms in DAiDAPI positive chromosomes, and the importance of Ag-NOR heteromorphisms to ascertain the maternal origin of the inv dup (15). A U-type exchange between two non-sister chromatids is proposed as its mechanism of formation. The clinical features of Ihe case were consistent with those previously reported in similar cases.