Other researchers have also demonstrated the association of HLA class I alleles with susceptibility to or protection from chronic hepatitis B. Thio et al. found that HLA-A*03:01 allele frequency was higher in Caucasian people, while HLA-B*08, both alone and as part of the conserved haplotype A*01-B*08, and HLA-B*44 allele frequencies were lower compared to patients with persistent HBV infection [12]. This evidence concerns the gene HLA-A and chronic hepatitis B virus infection.