[Genetic analysis of two patients with a rare Ael subtype].

OBJECTIVE: To analyze the genetic sequences of two patients with a rare Ael blood subgroup. METHODS: Two female patients undergoing treatment respectively for adenomyoma of the uterus and gastritis at the Second Affiliated Hospital, Yuying Children's Hospital of Wenzhou Medical University in June 2019 and September 2020 were selected as the study subjects. Their Ael subtypes were identified with a saline tube agglutination assay and absorption-emission assay. Sequence of the ABO gene Ael subtypes was determined by the Sanger method. The impact of genetic variants on the structural stability of N-acetylgalactosaminyl transferase (GTA) was analyzed with PyMOL software by constructing a structure predicted model. RESULTS: Both patients were determined as Ael blood subgroup. Sequencing result of patient 1 was ABO*O.01.02/ABO*O.01.02, which has resulted in a p.Thr88Profs*31 amino acid substitution. The sequencing result of patient 2 was ABO*Ael.06/ABO*O.01.02, in which c.425C>T and c.467C>T variants in exon 7 have led to p.Met142Thr and p.Pro156Leu substitutions. Prediction of the protein model speculated that the p.Met142Thr not only can change the binding of GTA protein with water molecules, but also the local hydrogen bond network of GTA, which may lead to decreased enzymatic activity. By contrast, the p.Pro156Leu variant has trivial effect on the structural stability of GTA. CONCLUSION: The molecular structure of Ael subtypes can be diverse. The genotypes of the two patients have been respectively determined as ABO*O.01.02/ABO*O.01.02 with a G261 deletion and ABO*Ael.06/ABO*O.01.02.

[Genetic identification and sequence analysis of three individuals of rare ABO variant Bw subgroup].

OBJECTIVE: To identify and analysis three ABO variant Bw subtypes. METHODS: Serological assays were carried out to identify the ABO blood group of the proband. ABO gene was identified by Sanger sequencing. RESULTS: The genotype of three individuals are ABO*Bw.11/0.01.02, ABO*Bw.12/0.01.01, ABO*Bw.34/A1.02, receptively. Sequencing results showed that there were c.695T>C, c.278C>T, c.889G>A, resulting in variants in Leu232Pro, Pro93Leu and Glu297Lys, receptively. CONCLUSION: Bw11, Bw12 and Bw34 subgroups were identified, and gene testing can be used as a supplement to determine the ABO blood group subtypes.

Sequence analysis of α-(1, 2)-fucosyltransferase gene in nine Chinese individuals with Para-Bombay phenotype.

BACKGROUND: To analyze the sequence of α-(1, 2)-fucosyltransferase gene (FUT1) in nine individuals with Para-Bombay phenotype. METHODS: Para-Bombay phenotype was defined according to the serologic characteristics and ABO genotypes. The full coding region of FUT1 was amplified, genotype and haplotype were analyzed by direct and TOPO cloning sequencing which was used to discriminate heterozygous mutations of FUT1. RESULTS: These nine individuals were identified as three Para-Bombay A (Ah), six Para-Bombay B (Bh) according to serologic characteristics and ABO genotypes. According to the direct and cloning sequencing results of the full coding region of FUT1, five genotypes and five haplotypes were found in these nine individuals. CONCLUSION: Two complex mutations of FUT1 were discovered, which were h1h547 - 552delAG + 814A > G (c.547 - 552delAG, p.Arg183Argfs ∗ 86; c.547 - 552delAG, p.Arg183Argfs ∗ 86 + c.814A > G, p.lle272Val) and h755G > Ch547 - 552delAG + 755G > C (c.755G > C, p.Arg183Argfs ∗ 86; c.547 - 548delAG, p.Arg183Argfs ∗ 86 + c.755G > C, p.Arg253Pro), the genotype of h755G > Ch547 - 552delAG + 755G > C was reported for the first time, and three kinds of known genotype (h1h1, h3h3, h1h3) were found also in these nine Chinese individuals with Para-Bombay phenotype in the present study. In this way, the FUT1 mutation showed a distinct geographic and ethnic range.

Genetic Sequencing Analysis of A307 Subgroup of ABO Blood Group.

BACKGROUND The aim of this study was to investigate the serology and gene sequence characteristics of the A307 subgroup of the ABO blood group. MATERIAL AND METHODS Monoclonal anti-A and anti-B antibodies were used to detect the ABO antigens of a proband whose positive blood type was not consistent with the negative blood type of the ABO blood group. Standard A-, B-, and O-negative typing cells were used to test for ABO antibodies in the serum. Additionally, polymerase chain reaction with sequence-specific primer (PCR-SSP) was used to confirm the genotype, and subsequently, exons 6 and 7 of the ABO gene were detected by gene sequencing. Samples from the wife and daughters of the proband were also used for serological and genetic testing. RESULTS Red blood cells of the proband showed weak agglutination reaction with anti-A antibody, while anti-B antibody was detected in the serum. Moreover, PCR-SSP detected A307 and O02 alleles, while gene sequencing revealed mutation of c.745C>T in exon 7, which produced a polypeptide chain p.R249W. The A307 gene of the proband was not inherited by his daughters. CONCLUSIONS A mutation (c.745 C>T) in exon 7 of the ABO blood group gene resulted in low activity of a-1,3-N-acetyl-galactosaminyl transferase, producing A3 phenotype.

Genetic sequencing analysis of the A307 subgroup of ABO blood group.

The aim of this study was to investigate the serology and gene sequence characteristics of the A307 subgroup of ABO blood group. Monoclonal anti-A and anti-B antibodies were used to detect the ABO antigens of a proband whose positive blood type was not consistent with the negative blood type of ABO blood group. Meanwhile, standard A-, B-, and O-negative typing cells were used to test for ABO antibodies in the serum. Additionally, polymerase chain reaction with sequence-specific primer (PCR-SSP) was used to confirm the genotype, and subsequently, exons 6 and 7 of the ABO gene were detected by gene sequencing. Samples from the wife and daughters of the proband were also used for serological and genetic testing. Red blood cells of the proband showed weak agglutination reaction with anti-A antibody, while anti-B antibody was detected in the serum. Moreover, PCR-SSP detected A307 and O02 alleles, while gene sequencing revealed mutation of c.745C>T in exon 7, which produced a polypeptide chain p.R249W. Furthermore, the A307 gene of the proband was not inherited by his daughters. A mutation (c.745 C>T) in exon 7 of the ABO blood group gene resulted in low activity of α-1, 3-N-acetyl-galactosaminyl transferase, producing A3 phenotype.

[Genetic analysis of an individual with para-Bombay phenotype].

OBJECTIVE: To study genetic characteristics of an individual with para-Bombay phenotype and her family members. METHODS: ABO and H antigens were detected with routine serological techniques.The entire coding region of FUT1 gene was amplified by polymerase chain reaction (PCR). PCR products was purified with enzymes digestion and directly sequenced. RESULTS: The RBCs of the proband did not agglutinate with H antibody. The proband therefore has a para-Bombay phenotype (Bmh). Direct sequencing indicated the FUT1 sequence of the proband contained a homozygous 547-552 del AG and heterozygous 814A>G mutation, which gave rise to two haplotypes of 547-552delAG, 547-552delAG and 814A>G. The ABO blood type of the proband' s mother and sisters were all B.Sequencing of the FUT1 gene has found heterozygous 547-552 del AG, 814A>G mutations in the mother and elder sister, and heterozygous 547-552 del AG mutation in her younger sister. The FUT1 547-552 del AG and 814 A>G mutations of the proband were inherited from her mother. CONCLUSION: A complex mutation of the FUT1 gene consisting of 547-55 del AG and 814 A>G has been identified in an individual with para-Bombay phenotype.