Rapid detection of fetal Mendelian disorders: thalassemia and sickle cell syndromes.
The inherited disorders of hemoglobin synthesis constitute the most common monogenic diseases worldwide. The clinical severity of beta-thalassemia major and the sickle cell syndromes targets them as priority genetic diseases for prevention programs, which incorporates population screening to identify heterozygotes,with the option of prenatal diagnosis for carrier couples. Rapid genotype characterization is fundamental in the diagnostic laboratory, especially when offering prenatal diagnosis. The application of real-time polymerase chain reaction (PCR) provides a means for rapid and potentially high-throughput assays, without compromising accuracy. It has several advantages over endpoint PCR analysis, including the elimination of post-PCR processing steps and a wide dynamic range of detection with a high degree of sensitivity. Although there are >180 mutations associated with the beta- thalassemia and sickle cell syndromes, the relatively small size of the beta-globin gene (<2,000 base pairs) and the proximity of most mutations facilitates the design of a minimal number of real-time PCR assays by using the LightCycler system (Roche Diagnostics [Hellas] A.E., Athens, Greece), which are capable of detecting the majority of most common beta-gene mutations worldwide. These assays are highly appropriate for rapid genotyping of parental and fetal DNA samples with respect to beta-thalassemia and sickle cell syndromes.
Traeger-Synodinos
Joanne
J
Department of Medical Genetics, National and Kapodistiran University of Athens, St. Sophia's Children's Hospital, Athens, Greece.
Vrettou
Christina
C
Kanavakis
Emmanuel
E
D000649:Amniocentesis; D000755:Anemia, Sickle Cell / Q000175:diagnosis* / Q000235:genetics; D005260:Female; D018507:Gene Expression Regulation, Developmental; D005820:Genetic Testing; D005914:Globins / Q000235:genetics*; D006801:Humans; D009154:Mutation; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D015203:Reproducibility of Results; D013577:Syndrome; D013789:Thalassemia / Q000175:diagnosis* / Q000235:genetics; D013997:Time Factors
D005914:Globins