IgA2 genotyping by polymerase chain reaction (PCR) using allele-specific amplification primers

Area of Science:

• Genetics
• Molecular Biology
• Forensic Science

Background:

• The human immunoglobulin alpha 2 heavy chain constant region (C alpha 2 gene) plays a role in immune responses.
• Accurate genotyping of IgA2 alleles is crucial for genetic and forensic studies.
• Existing methods may have limitations in sensitivity or sample applicability.

Purpose of the Study:

• To develop a novel genotyping method for IgA2 alleles.
• To validate the method's accuracy and sensitivity using DNA samples.
• To assess the utility of the developed method in forensic applications.

Main Methods:

• Developed a nested polymerase chain reaction (PCR) assay utilizing allele-specific primers.
• Discriminated base substitutions in the 3'-flanking region of A2m*1 and A2m*2 alleles.
• Detected IgA2 genotypes (IgA2*1/IgA2*1, IgA2*2/IgA2*1, IgA2*2/IgA2*2) from DNA extracted from lymphocytes.

Main Results:

• The PCR method successfully genotyped IgA2 alleles with high sensitivity, requiring as little as 100 pg of DNA.
• Genotyping was feasible from various biological sources, including blood, saliva, and tissue samples.
• Analysis of 318 Japanese subjects yielded allele frequencies of 0.561 for IgA2*1 and 0.439 for IgA2*2.
• Paternity testing data supported Mendelian inheritance patterns for IgA2 alleles.

Conclusions:

• The developed PCR-based method provides a sensitive and versatile tool for IgA2 genotyping.
• The method is suitable for diverse forensic applications, including paternity testing and individual identification.
• This advancement contributes to the field of human genetic analysis and forensic science.