{'fraction_non_alphanumeric': 0.022448979591836733, 'fraction_numerical': 0.012244897959183673, 'mean_word_length': 4.839285714285714, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Association of genes within the major histocompatibility complex with attention deficit hyperactivity disorder.

The objective was to determine whether a relationship exists among the complement C4B gene, a DR region gene and attention deficit hyperactivity disorder (ADHD). Thirty-one subjects with ADHD, their mothers, all but 5 of their fathers, and 90 normal subjects living in northern Utah were studied. DR and C4B typing were performed by serologic HLA typing techniques and the DNA methods PCR-RFLP. The alleles of 2 genes, the null allele of the C4B gene and the beta 1 allele of the DR gene, encode for products involved in immune function and regulation. Each of these alleles was found to be significantly associated with ADHD. Moreover, approximately 55% of the ADHD subjects carried both of these alleles on 1 of their chromosomes, compared to only 8% of normal controls. Genes related to the immune system may be associated with development of the symptoms of ADHD.