Comprehensive cytogenetic analysis of cases referred for suspected chromosomal abnormalities: A Five-year study at Advanced Medical and Dental Institute (AMDI), Universiti Sains Malaysia, Penang, Malaysia.
Keywords:
Chromosomal abnormalities, cytogenetics, karyotypeAbstract
Chromosomal abnormalities (CA) can affect numerical or structural compositions of chromosomosal DNA leading to a diversity of clinical phenotypic presentations. Awareness of prenatal diagnosis and genetic counselling have improved with advancing medical research but CA remain prevalent as its aetiology is unknown. The objective of this study is to determine the frequencies of various CA in the principle region of north-western Malaysia and compare this data to previous reports to ascertain if statistical differences exist. Karyotype analyses performed at the Genetics Laboratory, Advanced Diagnostic Laboratory (ADL) during the first 5-years of cytogenetic services, totalling 1461 cases, were assessed in this report. Cases suspected of CA were initially diagnosed by clinicians and detailed clinical and family histories were recorded. Peripheral blood lymphocytes of patients were collected and cultured in vitro for acquisition of karyotype by standardized G-banding technique. Fluorescence in situ hybridization (FISH) was conducted in cases suspected of to be DiGeorge, Prader-Willi, Angelman and Williams syndrome. Of the total samples (1805) received and cultured, 1669 (92.46%) successfully yielded results. Abnormal outcomes were observed in 495 cases (29.66%) whereby pronounced majority of cases 299 (68.42%) were Down syndrome. This is followed by Edward, Turner and Patau syndrome, in order of frequency. Numerical CA appears to be prevalent accounting for 85.86% of cases. Structural CA accounted for 14.14% of total positive cases whereby the most common was deletions (34.29%) followed by translocations (20%), ring chromosomes (5.71%), Fragile X syndrome (4.29%), duplications (5.71%) and marker chromosomes (7.14%). The remainder of cases (22.86%) consisted of derivative chromosomes and other complex aberrations. The number of polymorphic variant cases were 27 (1.62%). The number of peripheral blood samples received has significantly increased from 14.3 per month in 2006 to 32.17 per month in 2011. Comparative analysis of our study to previous reports reveal statistical differences in the occurrence of several CA including Edward, Patau, Klinefelter and Fragile-X syndrome. Our experience with peripheral blood samples for cytogenetic analysis demonstrated a success rate of 92.46%. This showed an increase in clinicians validating patients’ diagnoses with karyotyping which is essential in confirming genetic anomalies with the goal to substantiate genetic counselling.References
LG Shaffer, LJ Campbell, ML Slovak (2009). ISCN 2009: An International System for Human Cytogenetic Nomenclature. 1st ed. Karger: Basel; 2009.
RS Verma, H Dosik (1980). Incidence of major chromosomal abnormalities in a referred population for suspected chromosomal aberrations: a report of 357 cases. Clinical Genetics. [Online] 17, pp. 305-308.
WS Choi, KH Kim, YK Paik (1984). A cytogenetic study in patients referred for suspected chromosomal abnormalities. Journal of Hanyang Medical College. [Online] 4, pp. 565-597.
SS Kim, SC Jung, HJ Kim, HR Moon, JS Lee (1999). Chromosome abnormalities in a referred population of suspected chromosomal aberrations: a report of 4117 cases. Journal of Korean Medical Science. [Online] 14, pp. 373-376.
M Balkan, H Akbas, H Isi, D Oral, A Turkyilmaz, S Kalkanli, et al. (2010). Cytogenetic analysis of 4216 patients referred for suspected chromosomal abnormalities in Southeast Turkey. Genetics and Molecular Research. [Online] 9(2), pp. 1094-1103.
SN Heyn, D Perlstein, editors. Down Syndrome [monograph on the internet]. California: eMedicineHealth, WebMD; 2011 [cited 2011 Oct 10]. Available from: http://www.emedicinehealth.com/down_syndrome/article_em.htm/.
EB Hook, JL Hamerton (1977). The frequency of chromosome abnormalities detected in consecutive newborn studies, differences between studies, results by sex and by severity of phenotypic involvement. In: Hook EB, Porter IH, editors. Population cytogenetics: studies in humans. New York: Academic Press; [Online] pp. 63-79.
J Nielsen, M Wohlert (1991). Chromosome abnormalities found among 34910 newborn children: results from a 13-year incidence study in Arhus, Denmark. Human Genetics. [Online] 87, pp. 81-83.
Genetics Home Reference [homepage on the Internet]. Bethesda, MD: Trisomy 13, U.S. National Library of Medicine; c2009-11 [updated 2009 Jan; cited 2011 Oct 10]. Available from: http://ghr.nlm.nih.gov/condition/trisomy-13#definition/.
Genetics Home Reference [homepage on the Internet]. Bethesda, MD: Trisomy 18, U.S. National Library of Medicine; c2009-11 [updated 2009 Jan; cited 2011 Oct 10]. Available from: http://ghr.nlm.nih.gov/condition/trisomy-18#definition/.
Spalding J., Genetics Mosaics Support Group [monograph on the internet]. Laurel, MD: xyTurners; 2004 [cited 2011 Oct 10]. Available from: http://www.xyxo.org/index.html/.
[ National Institute of Child Health & Human Development [homepage on the Internet]. Bethesda, MD: U.S. National Institutes of Health; c2007-11 [updated 2007 May 24; cited 2011 Oct 10]. Available from: http://www.nichd.nih.gov/health/topics/klinefelter_syndrome.cfm/.
Genetics Home Reference [homepage on the Internet]. Bethesda, MD: Turner Syndrome, U.S. National Library of Medicine; c2008-11 [updated 2008 May; cited 2011 Oct 10]. Available from: http://ghr.nlm.nih.gov/condition/turner-syndrome#definition/.
JA Jewell, B Buehler, editors. Fragile X Syndrome [monograph on the internet]. California: Medscape Reference, WebMD; 2011 [cited 2011 Oct 10]. Available from: http://emedicine.medscape.com/article/943776-overview#a0101/.
Genetics Home Reference [homepage on the Internet]. Bethesda, MD: Fragile X Syndrome, U.S. National Library of Medicine; c2007-11 [updated 2007 May; cited 2011 Oct 10]. Available from: http://ghr.nlm.nih.gov/condition/fragile-x-syndrome#definition/.
FI Sahin, Z Yilmaz, OO Yuregir, T Bulakbasi, O Ozer, HB Zeyneloglu (2008). Chromosome heteromorphism an impact on infertility. J Assist Reprod Genet. [Online] 25, pp. 191–195.
AR Brothman, NR Schneider, I Saikevych, LD Cooley, MG Butler, S Patil, et al. (2006). Cytogenetic heteromorphisms: Survey results and reporting practices of Giemsa-band regions that we have pondered for years. Arch Pathol Lab Med. [Online] 130(7), pp. 947–949.
K Yakin, B Balaban, B Urman (2005). Is there a possible correlation between chromosomal variants and spermatogenesis?. International Journal of Urology. [Online] 12, pp. 984-989.
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