Author/Editor		Erjavec Škerget, Alenka; Stangler Herodež, Špela; Zagorac, Andreja; Zagradišnik, Boris; Kokalj-Vokač, Nadja
Title		Uporaba primerjalne genomske hibridizacije kot diagnostične metode v medicinskem genetskem laboratoriju
Translated title		The use of comparative genomic hybridization as a diagnostic tool in medical genetics laboratories
Type		članek
Vol. and No.		Letnik 4, št. 1
Publication year		2011
Volume		str. 49-56
ISSN		1855-5640 - Acta medico-biotechnica : AMB
Language		eng
Abstract		Namen: Primerjalna genomska hibridizacija (PGH) je molekularno citogenetska tehnika za identifikacijo kromosomskih neravnovesij po celotnem genomu. Zaradi njene kompleksnosti jo kot rutinsko diagnostično metodo uporablja samo nekaj laboratorijev po svetu. Predstaviti želimo svoje izkušnje pri delu s tehniko PGH in njeno diagnostično uporabnost pri post-natalnih kliničnih vzorcih. Metode: Validacijo PGH tehnike smo opravili na vzorcu 10 preiskovancev z diagnozo nepojasnjena mentalna retardacija in s predhodno določenimi subtelomernimi kromosomskimi spremembami v velikostnem razredu 3,9 do 37 Mbp. Kot potrditveno metodo za določitev kromosomske aneuploidije smo PGH uporabili pri petih vzorcih embrionalnega tkiva po spontanih splavih. Pri enajstih hematoloških onkoloških vzorcih smo PGH uporabili pri razreševanju kompleksno preurejenih kariotipov. Rezultati: S PGH smo našli subtelomerne kromosomske spremembe, večje od 8 Mbp. Z metodo PGH smo potrdili vse z molekularno kariotipizacijo predhodno najdene kromosomske aneuploidije v embrionalnih tkivih po spontanih abortusih, kjer celice niso bile več mitotsko aktivne. Največja uporabnost PGH se je pokazala pri pojasnjevanju kompleksnih kromosomskih preureditev v primerih hematoloških malignih obolenj. Zaključek: Čeprav je PGH tehnično zahtevna in zamudna tehnika in kot taka neprimerna za rutinsko diagnostično delo, je po naših izkušnjah nepogrešljiva v posameznih primerih, v katerih druge genetske analize niso uporabne, npr. pri mitotsko neaktivnem celičnem materialu ali pri kompleksno preurejenih kariotipih. Naše izkušnje in rezultati potrjujejo njeno uporabnost predvsem v tistih genetskih laboratorijih, kjer zaradi ekonomskih razlogov še niso uspeli vpeljati pregledovanja genoma na osnovi t.i. micro-array tehnologije.Purpose: Comparative genomic hybridization (CGH) is a molecular- cytogenetic technique used to identify chromosomal imbalances throughout a genome. Due to its complexity, the use of CGH as a regular diagnostic technique is limited to only a few diagnostic laboratories. In this study, we evaluated the potential applications of CGH as a diagnostic method in different post-natal clinical samples. Methods: Ten patients were recruited with submicroscopic chromosomal abnormalities ranging in size from 3.9 to 37 Mb. For the purpose of confirmation, CGH was applied to five cases where molecular karyotyping with MLPA was previously utilized to detect chromosome aneuploidy. To date, CGH was largely used for the identification of the complex karyotype in haematological malignancies. Results: In eight cases of haematological malignancies, we were able to resolve complex karyotypes with CGH. Utilizing CGH as a diagnostic tool, we detected chromosomal imbalances larger than 8 Mb. In addition, we confirmed all chromosomal aneuploidies that were previously detected with MLPA from embryonic tissues obtained from aborted fetuses. In this tissue, the cells were not mitotically active, and therefore, were inappropriate for the conventional cytogenetics. Conclusion: Because CGH is technically demanding and time consuming, this technique is likely to be inappropriate for screening purposes. However, we found that CGH may be very useful in sporadic cases, where the sample material is not mitotically active or in cases with complex karyotypes. Therefore, our results confirmed that CGH may be useful in laboratories that are unable to use micro-array CGH for economic reasons.
Keywords		primerjalna genomska hibridizacija medicinska genetika diagnostična metoda comaprative geonimc hybridization medical genetics diagnostic method