[Retrospective Analysis of Hematological Phenotypes in Patients with Gene Mutation and Deletion α-Thalassemia].

OBJECTIVE: To explore the differences between hematological phenotypes of patients with different genotypes in gene mutations and deletion α- thalassemia. METHODS: By screening the α- thalassemia gene test results in the First Affiliated Hospital, Sun Yat-Sen University from January 2015 to April 2020, the patients with mutation and deletion α- thalassemia were obtained, then the differences between hematological phenotypes of patients with different genotypes were analyzed. RESULTS: There were 96 patients with mutation combined with deletion α- thalassemia from the results of 24 054 α- thalassemia patients screened out, including 79 patients with non-deletion Hb H disease (αTα/--SEA) and 17 patients with mild α- thalassemia (αTα/-α), the incidence was 0.42%. Except the number of red blood cells (RBC) and mean corpuscular volume (MCV), the hemoglobin (Hb) concentration, hematocrit (Ht), average red blood cell hemoglobin concentration (MCHC), average red blood cell hemoglobin amount (MCH), average red blood cell volume (MCV) of the patients with αTα/--SEA genotype were significantly lower than those with αTα/-α genotype. The Hb of the patients with αCSα/--SEA and αQSα/--SEA genotype was (86±20)g/L and (84±9)g/L, respectirely, which was significantly lower than (114±16) g/L of αWSα/--SEA genotype (P<0.05); The MCHC of patients with αCSα/--SEA and αQSα/--SEA genotype was (278.8±8.5) g/L and (282.1±21.1)g/L, respectirely, which was also significantly lower than (315.4±19.5) g/L of αWSα/--SEA genotype (P<0.05); There was no significant difference between the patients with αCSα/--SEA and αQSα/--SEA genotype in hematological phenotypes. Except MCH and MCV, there was no significant differences between the patients with αWSα/--SEA and αTα/-α genotype in RBC, Hb, and Ht. The result of Hb A2 was (2.3±0.9)% for only 27 patients who performed electrophoretic analysis. There was no significant difference between the patients with αTα/--SEA and αTα/-α genotype in Hb A2, aslo among 3 types of the patients with αTα/--SEA genotype. CONCLUSION: The hematological phenotype changes caused by αWSα/--SEA genotype are similar to those of mild α- thalassemia, and both of them are significantly lighter than those patients with αCSα/--SEA and αQSα/--SEA genotype.

[Analysis on mutation of adrenoleukodystrophy gene in exon 1 and exon 5].

OBJECTIVE: To elucidate the molecular mechanism of X-linked adrenoleukodystrophy(ALD) in Chinese. METHODS: Polymerase chain reaction in exon 1, exon 5 and their flanking sequences and direct DNA sequencing of ALD gene were performed in four patients, their mothers and twenty normal individuals as controls. RESULTS: A splice mutation was identified in the interface of exon 5 and intron 5 (1875 G-->A). This splice mutation in 5' end of intron 5 might lead to abnormal splice in exon 5 and exon 6 and bring about unstable and abnormal ALD protein; the lignoceryl CoA ligase could not transport very long chain fatty acids (VLCFA) into peroxisome and could not function normally; consequently, defective beta-oxidation of VLCFA in peroxisome could result in an accumulation of VLCFAS in the central nervous system, adrenal gland and blood. CONCLUSION: The splice mutation in 5' end of intron 5 leading to abnormal splice in exon 5 and exon 6 appears to be one of the causes of X-linked recessive adrenoleukodystrophy.