Diagnosis and clinical phenotype analysis of a case with large fragment homozygous deletion of rare β gene cluster / 中华医学遗传学杂志

OBJECTIVE@#To report on a case with homozygous deletion of large β gene cluster and its clinical characteristics.@*METHODS@#A total of 71 001 peripheral blood samples were subjected to capillary electrophoresis and conventional testing for common thalassemia mutations. The genotypes of suspected β gene cluster deletions were analyzed by Gap-PCR and multiplex ligation-dependent probe amplification (MLPA). Their hematological characteristics were compared by statistical analysis R software.@*RESULTS@#Eighty-nine cases were detected with Chinese @*CONCLUSION@#The carrier rate for large fragment deletions of β gene cluster in Huizhou region is rather high, for which the value of HbF is significantly increased. Attention should be paid to screening and diagnosis of rare genotype to prevent missed diagnosis and/or misdiagnosis.

Phenotypic and genotypic analysis of 45 cases with Hemoglobin Q-Thailand / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore hematological and molecular characteristics of Hemoglobin Q-Thailand in Huizhou area of Guangdong Province.</p><p><b>METHODS</b>A total of 34 977 samples were screened by capillary and agarose gel electrophoresis. Samples suspected with HbQ strips were subjected to blood cell count and DNA sequencing. Twenty three common mutations associated with α- and β-thalassemia were identified by liquid phase chip and diversion hybridization technique.</p><p><b>RESULTS</b>The carrier rate of Hb Q-Thailand in Huizhou area was 0.13%. Pedigree analysis indicated that the Hb Q-Thailand allele is linked with a leftward single a-globin gene deletion (-α). Hematological index (HGB, MCV, MCH, HbA, HbA, HbQ) of 45 heterozygous carriers of Hb Q-Thailand were (130.25±17.37) g/L, (79.81±4.97) fl, (26.38±1.48) pg, (71.37±5.07)%, (1.65±0.45)%, (26.87±4.95)%, respectively. A statistical difference was also found in their hematological index of HbA and HbA compared with 408 heterozygous carriers of -α mutation (P<0.05).</p><p><b>CONCLUSION</b>Hb Q-Thailand has a high detection rate in Huizhou area. The allele is mainly in a heterozygous status and linked with -α. The Hb Q strip can be detected by hemoglobin electrophoresis. When combined with other types of thalassemia, the heterozygotes will show unique hematological parameters.</p>