An application of PCR-single strand conformation polymorphism to MN genotyping

Area of Science:

• Genetics
• Anthropology
• Forensic Science

Background:

• The MN blood group system, determined by the glycophorin A (GPA) gene, is crucial for human identification and population studies.
• Previous genotyping methods for the MN blood group system have limitations in discriminating specific alleles.

Purpose of the Study:

• To develop and validate a PCR-based genotyping method for the MN blood group system.
• To analyze the allele frequencies of the MN blood group system in a northern Japanese population.
• To assess the utility of this genotyping method for paternity testing.

Main Methods:

• DNA samples from 409 northern Japanese individuals were analyzed.
• A 257bp DNA fragment of the GPA gene (exon 2) was amplified using PCR.
• PCR-single-strand conformation polymorphism (PCR-SSCP) was employed for genotyping.
• Allele frequencies and statistical parameters (polymorphism information content, paternity exclusion probability) were calculated.

Main Results:

• The PCR-SSCP method successfully discriminated M alleles into M(G) and M(T).
• Three patterns were observed for N alleles: N(1), N(2), and N(V), with N(1) being predominant.
• N(2) exhibited two base substitutions, while N(V) showed one substitution in intron 2.
• Calculated allele frequencies for M(G), M(T), N(1), and N(2) were 0.4450, 0.0978, 0.4303, and 0.0269, respectively.
• Polymorphism information content was 0.5252, and paternity exclusion probability was 0.3219.

Conclusions:

• The developed PCR-based genotyping method is effective for analyzing the MN blood group system.
• This method provides valuable genetic data for the northern Japanese population.
• The genotyping method demonstrates potential for applications in forensic science, including paternity testing.