Diagnosis of four chromosome abnormalities of unknown origin by chromosome microdissection and subsequent reverse and forward painting

Katia Édni F De Albuquerque CoêlhoMasayuki EgashiraRumiko KatoMasahiro FujimotoNaomichi MatsumotoBudsaba RerkamnuaychokeKyohko AbeNaoki HaradaHirofumi OhashiYoshimitsu FukushimaNorio NiikawaNagasaki University School of MedicineKyushu Medical Science Nagasaki LaboratorySaitama Children's Medical CenterMahidol University2018-07-042018-07-041996-06-14American Journal of Medical Genetics. Vol.63, No.3 (1996), 468-471014872992-s2.0-0029950243https://repository.li.mahidol.ac.th/handle/20.500.14594/17728A molecular cytogenetic method consisting of chromosome microdissection and subsequent reverse/forward chromosome painting is a powerful tool to identify chromosome abnormalities of unknown origin. We present 4 cases of chromosome structural abnormalities whose origins were ascertained by this method. In one MCA/MR patient with an add(5q)chromosome, fluorescence in situ hybridization (FISH), using probes generated from a microdissected additional segment of the add(5q) chromosome and then from a distal region of normal chromosome 5, confirmed that the patient had a tandem duplication for a 5q35- qter segment. Similarly, we ascertained that an additional segment of an add(3p) chromosome in another MCA/MR patient had been derived from a 7q32- qter segment. In a woman with a history of successive spontaneous abortions and with a minute marker chromosome, painting using microdissected probes from the whole marker chromosome revealed that it was i(15)(p10) or psu dic(15;15)(q11;q11). Likewise, a marker observed in a fetus was a ring chromosome derived from the paracentromeric region of chromosome 19. We emphasize the value of the microdissection-based chromosome painting method in the identification of unknown chromosomes, especially for marker chromosomes. The method may contribute to a collection of data among patients with similar or identical chromosome abnormalities, which may lead to a better clinical syndrome delineation.Mahidol UniversityMedicineNeurosciencePsychologyDiagnosis of four chromosome abnormalities of unknown origin by chromosome microdissection and subsequent reverse and forward paintingArticleSCOPUS10.1002/(SICI)1096-8628(19960614)63:3<468::AID-AJMG10>3.0.CO;2-K