Semi-nested Taqman real-time quantitative PCR for noninvasive prenatal diagnosis of Bart's hydrops fetalis.

Background: Non-invasive prenatal diagnosis based on detection of fetal cell-free DNA is limited when mother and father are both carriers for the same autosomal recessive mutation.

Objective: Develop the semi-nested Taqman real-time PCR for quantification of alpha-thalassemia-1 SEA type deletion allele in plasma of alpha-thalassemia-1 SEA carriage pregnancies.

Material And Method: Plasma DNA was extracted from six women who carried fetuses with normal, 11 with heterozygote alpha-thalassemia-1 SEA type deletion and seven with Bart's hydrops fetalis.

Interference of hemoglobin Hope on beta-thalassemia diagnosis by the capillary electrophoresis Method.

The β-chain hemoglobin (Hb) variants interfere with the diagnosis of β-thalassemia trait using high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE). We analyzed the effect of Hb Hope, a β-chain Hb variant frequently found in the Thai population, on β-thalassemia trait diagnosis. HPLC and CE were used to quantify the level of HbA(2) in 11 whole blood samples containing Hb Hope.

Analysis of real-time PCR cycle threshold of alpha-thalassemia-1 Southeast Asian type deletion using fetal cell-free DNA in maternal plasma for noninvasive prenatal diagnosis of Bart's hydrops fetalis.

Background: Noninvasive prenatal diagnosis based on detection of fetal cell-free DNA is hampered when mother and father are both carriers for the same autosomal recessive mutation.

Objective: To compare the diagnosis of Bart's hydrops fetalis using conventional Gap-PCR analysis of fetal cells/tissues with the measurement of quantitative difference (deltaCp) between alpha-thalassemia-1 SEA type deletion gene (C(T-mutant)) and wild type alpha-globin gene (C(T-wild type)) in plasma of pregnancies by using the Taqman real-time quantitative PCR.

Material And Method: Plasma DNA samples were collected from three groups of pregnancies whose fetuses have known thalasemia status (7 normal, 11 heterozygote alpha-thalassemia-1 SEA type deletion, and 7 Bart's hydrops fetalis).

Diagnosis of thalassemia on dried blood spot samples by high performance liquid chromatography.

High performance liquid chromatography (HPLC) on fresh lysates is the standard test for identification of thalassemia. Samples in the form of dried blood spot(s) (DBS) mailed to reference laboratories where HPLC is available could be an alternative. Hemoglobin (Hb) on DBS at day 1, 7, 15 and 30 were analyzed by HPLC and compared to those analyzed from fresh liquid whole blood at day 0.

SYTO9 and SYBR GREEN1 with a high-resolution melting analysis for prenatal diagnosis of β⁰-thalassemia/hemoglobin-E.

The β⁰-thalassemia/Hb-E causes a wide range of severe conditions. A high medical cost is incurred in severe cases. Thus, the prevention of new cases of β⁰-thalassemia/Hb-E is required.

SYTO9 and SYBR GREEN1 with high resolution melting analysis for molecular confirmatory testing of the common Southeast Asian beta(0)-thalassemia mutations.

Gel electrophoresis and ethidium bromide staining are routine methods in molecular laboratories. However, they are not ideally suited to large scale analyses in clinical laboratories. We used SYTO9 and high resolution melting (HRM) analyses for identification of the common beta(0)-thalassemia (beta(0)-thal) in Southeast Asia including the codons 17 (A>T), 41/42 (-TCTT) and 71/72 (+A) mutations.

Increased Hb A2 values in an HIV-1-infected patient receiving antiretroviral drugs: a pitfall for thalassemia antenatal diagnosis.

We report a human immunodeficiency virus-1 (HIV-1)-infected couple, where the woman in the 11th week of gestation, carried a Hb E trait. She and her spouse were referred to the hemoglobinopathy counselors. Her spouse's blood was subsequently tested and showed an increased Hb A(2) value.

Analysis of real-time SYBR-polymerase chain reaction cycle threshold for diagnosis of the alpha-thalassemia-1 Southeast Asian type deletion: application to carrier screening and prenatal diagnosis of Hb Bart's hydrops fetalis.

Without gel electrophoresis and specific probes, the two tubes real-time SYBR-polymerase chain reaction (SYBR-PCR) was setup by using different primer sets: P1/P2 for the detection of wild type alpha-globin gene alleles and P1/P3 for detection of the allele bearing the Southeast Asian (SEA) type (--SEA) deletion. Analyses of the cycle threshold (CT) values obtained by each primer set together with a delta-cycle threshold (DeltaCT) and CT ratio, showed that lower CT values generated by primer sets P1/P2 and P1/P3 were observed in normal and Hb Bart's hydrops fetalis subjects, respectively. In heterozygous subjects the CT values generated by both sets of primers were similar to each other.