Rapid molecular characterization of Hb Queens and Hb Siam: two variants easily misidentified as sickle Hb.
OBJECTIVE
To establish a rapid differential diagnosis of hemoglobin (Hb) Queens and Hb Siam from other clinically relevant variants.


METHODS
Molecular and hematological features associated with two pregnant Thai women who were mistaken for Hb S were investigated. A simultaneous DNA diagnosis based on multiplex allele specific PCR approach was developed and tested with other common variants.


RESULTS
Apart from mild anemia, the two subjects were generally healthy. DNA analysis identified that they were respectively carriers of Hb Siam [alpha15(A13)Gly-Arg] and Hb Queens [alpha34(B15)Leu-Arg]. A successful application of the multiplex allele specific PCR for differential diagnosis was demonstrated.


CONCLUSIONS
Diagnosis of these clinically relevant hemoglobinopathies is problematic in the routine setting, and the method developed should prove useful in complementing routine Hb analysis for providing accurate diagnosis.
Fucharoen
Supan
S
Centre for Research and Development of Medical Diagnostic, Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen 40002, Thailand. supan@kku.ac.th
Singsanan
Sanita
S
Hama
Abdulloh
A
Fucharoen
Goonnapa
G
Sanchaisuriya
Kanokwan
K
D000483:Alleles; D000755:Anemia, Sickle Cell / Q000175:diagnosis* / Q000235:genetics*; D003937:Diagnosis, Differential; D005260:Female; D006400:Hematocrit; D006451:Hemoglobin, Sickle / Q000235:genetics; D006455:Hemoglobins, Abnormal / Q000032:analysis / Q000235:genetics*; D006801:Humans; D016133:Polymerase Chain Reaction; D011247:Pregnancy
D006451:Hemoglobin, Sickle; D006455:Hemoglobins, Abnormal; C406708:hemoglobin Siam; C035047:hemoglobin Queens