[Noninvasive prenatal diagnosis of Hb Bart's hydrops fetus using cell-free fetal DNA in maternal plasma].

Objective: To explore a new noninvasive method for Hb Bart' s hydrops fetus by using PCR amplification efficiency discrimination between cell-free fetal DNA (cffDNA) and cell-free maternal DNA in maternal plasma.

Methods: CffDNA samples from pregnant women bearing possible Hb Bart's hydrops fetus were collected. Fluorescent PCR and capillary electrophoresis (CE) were performed.

[A study on the (CA)n in FVIII gene in Han ethnic group in Guangxi Zhuang Autonomous Region by amplification polymorphisms combined with silver staining].

Objective: Hemophilia A is an inherited bleeding disorder caused by defects in factor VIII (FVIII) gene. In the present study, the frequencies of the microsatellite alleles at introns 13 and 22 in the factor VIII gene were analyzed in the group of Han nationality in Guangxi Zhuang Autonomous Region to explore their diagnostic value for hemophilia A. These two sites were also used to detect the carriers in 13 hemophilia A families.

[Identification of fetal nucleated erythrocytes in maternal blood using short tandem repeat typing after primer extension preamplification].

Objective: To develop a method for identifying fetal nucleated erythrocytes (NRBCs) in maternal blood.

Methods: NRBCs in maternal blood were detected by benzidine staining and collected by micromanipulation. After primer extension preamplification (PEP) of the entire genome from a single NRBC, short tandem repeat (STR) genotype was analysed after further amplification of this gene.

[Relationship between the expression of murine double minute 2 oncogene and non-Hodgkin lymphoma in childhood].

Objective: To investigate the relationship between the expression of murine double minute 2 (MDM2) oncogene and non-Hodgkin lymphoma (NHL) in childhood.

Methods: Thirty-one cases of NHL were enrolled in this study as patient group and 8 cases of lymphadenitis as control group. (1) Immunohistochemistry ultrasensitive S-P assay was used to detect the expression of MDM2 protein in pathological tissues in all cases.

[Beta-thalassemia mutations and single nucleotide polymorphism at -158 of Ggamma-globin gene associated with altered levels of Hb F in beta-thalassemia heterozygotes].

Objective: To investigate the relationship of beta-thalassemia mutations and the single nucleotide polymorphism(SNP) at position -158 of (G)Gamma-globin gene to the altered levels of fetal hemoglobin(Hb F) of beta-thalassemia heterozygotes.

Methods: Hb F was quantitated by alkali denaturation; beta-thalassemia mutations were determined by PCR-allelic specific oligonucleotide(PCR-ASO). The SNP at -158 was analyzed by amplification of (G)Gamma gene promoter fragments from the DNA, followed by Xmn I restriction enzyme digestion.

[Homozygous hemoglobin constant spring in Guangxi province].

Objective: To analyze the relationship between genotype and phenotype of homozygous hemoglobin Constant Spring (Hb CS) in Guangxi province, and to explore the reasons of missed diagnosis and the methods for screening and diagnosing.

Methods: Screening Hb CS by acetate fibrous membrane electrophoresis with benzidine staining. Gene mutation of homozygous Hb CS by polymerase chain reaction (PCR) and DNA sequencing.