Abnormal melt curve profile during prothrombin 20210G --> A analysis due to the 20209C --> T variant.
The common factor II 20210G --> A mutation, located in the 3'-untranslated region, is an important risk factor for the development of thromboembolic disorders, especially in Caucasians. A number of methods are employed for clinical laboratory diagnosis of this mutation, some of which are capable of detecting adjacent 3'-end sequence variations. We present results from an African deep vein thrombosis patient tested for the 20210G --> A mutation by real-time polymerase chain reaction and melt-curve analysis using hybridization probes that incidentally detected an adjacent 3'-untranslated region variant. The patient sample was tested using the Factor II (Prothromobin) G20210A Kit (Roche Diagnostics, Indianapolis, Indiana, USA), in conjunction with the Roche LightCycler. A polymerase chain reaction fragment from the 3'-end of the F2 gene was subsequently sequenced for identification of the variant. Melt-curve analysis revealed a normal 20210*G peak and an unknown aberrant allelic peak. Following sequence analysis, the patient was determined to be heterozygous for 20209C --> T. The presence of the 20209C --> T variant in the current patient and in eight other reported individuals of African descent, most with thrombosis-associated complaints, suggests that this rare variant poses a potential increased risk for thromboembolic disease in this ethnic group.
Dunn
S Terence
ST
Molecular Pathology Laboratory, Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA. terry-dunn@ouhsc.edu
Allen
Richard A
RA
Bates
Francesca
F
McNamara
Victoria
V
Comp
Philip
P
D000328:Adult; D015342:DNA Probes / Q000737:chemistry; D005260:Female; D014644:Genetic Variation; D006579:Heterozygote; D006801:Humans; D009691:Nucleic Acid Denaturation; D009693:Nucleic Acid Hybridization; D017354:Point Mutation; D011516:Prothrombin / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012307:Risk Factors; D017422:Sequence Analysis, DNA / Q000379:methods; D013696:Temperature; D020246:Venous Thrombosis / Q000235:genetics*
D015342:DNA Probes; D011516:Prothrombin