Development and application of a real-time quantitative PCR for prenatal detection of fetal alpha(0)-thalassemia from maternal plasma.

Abstract

In order to provide a noninvasive prenatal diagnosis of alpha(0)-Thalassemia (Southeast Asian [SEA] deletion), we have developed a real-time quantitative semi-nested polymerase chain reaction (PCR) method for identifying the fetal alpha(0)-Thalassemia in maternal plasma. Analysis was performed using DNA extracted from 200 muL plasma from 13 pregnant women during 8-20 weeks of gestation who carried fetuses with normal (2), alpha(0)-Thalassemia carrier (8), Hb H disease (1), and homozygous alpha(0)-Thalassemia (Hb Bart's hydrops fetalis (2). The alpha(0)-Thalassemia was detected using a two-step PCR. Plasma DNA was amplified conventionally using alpha(0)-Thalassemia-specific primers and a portion of the first PCR product was subjected to a semi-nested real-time q-PCR using the SYBR green I chemistry for fluorescence detection. Calibration curve for alpha(0)-Thalassemia quantification was prepared by assaying serial dilution of genomic DNA of an alpha(0)-Thalassemia carrier. Differences in the C(T) (threshold cycle) values and calculated concentrations of amplified DNA among normal fetus, alpha(0)-Thalassemia carrier, Hb H disease, and homozygous alpha(0)-Thalassemia were clearly observed, which could help in prenatal prediction of the fetal genotype. This noninvasive prenatal detection of alpha(0)-Thalassemia in maternal plasma should enhance prenatal diagnostic options for this common genetic disorder in routine DNA diagnostic setting.

• Authors: Warunee Tungwiwat, Supan Fucharoen, Goonnapa Fucharoen, Thawalwong Ratanasiri, Kanokwan Sanchaisuriya
• Journal: Annals of the New York Academy of Sciences (Ann N Y Acad Sci) Vol. 1075 Pg. 103-7 (Sep 2006) ISSN: 0077-8923 [Print] United States
• PMID: 17108198 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• DNA

Topics

• DNA (blood)
• Female
• Humans
• Maternal-Fetal Exchange
• Polymerase Chain Reaction (methods)
• Pregnancy
• Prenatal Diagnosis
• Thailand
• alpha-Thalassemia (diagnosis, genetics)