Autoimmune regulator-1 messenger ribonucleic acid analysis in a novel intronic mutation and two additional novel AIRE gene mutations in a cohort of autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy patients.
BACKGROUND
Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare autosomal recessive disease associated with mutations in the AIRE gene.


OBJECTIVE
Our objective was to investigate clinical and mutational characteristics of 12 Slovenian patients from 10 families with APECED.


METHODS
Direct sequencing, restriction fragment length polymorphism, and amplification refractory mutation system analyses were used to identify AIRE gene mutations. Autoimmune regulator (AIRE)-1 mRNA analysis was used to confirm pathogenicity of the intronic mutation.


RESULTS
The prevalence of APECED in Slovenian population was estimated to be 1 in 43,000, which is significantly higher compared with the neighboring populations. Three novel mutations were identified among six different mutations detected in the AIRE gene. The first novel mutation was an intronic mutation (653-7_-5delCTC) affecting proper splicing by using a nearby new acceptor splice site as demonstrated by AIRE-1 mRNA analyses. The second and third novel mutations were frame-shift mutations located in exon 5 (540delG) and exon 9 (1064-1068dupCCCGG), both leading to premature truncation of the AIRE protein. The Finnish R257X mutation was the most frequent AIRE gene mutation in Slovenian patients with APECED (16 of 24 alleles).


CONCLUSIONS
Three novel AIRE gene mutations were identified. For the first time, a novel intronic mutation was investigated on the mRNA level in APECED. This could be particularly important for APECED patients where no or only heterozygous mutation on the genomic DNA level is detected.
Podkrajsek
Katarina Trebusak
KT
Centre for Medical Genetics, University Children's Hospital, Ljubljana, Vrazov trg 1, SI-1000 Ljubljana, Slovenia.
Bratanic
Nina
N
Krzisnik
Ciril
C
Battelino
Tadej
T
D000293:Adolescent; D000328:Adult; D001483:Base Sequence; D002648:Child; D015331:Cohort Studies; D004252:DNA Mutational Analysis; D005260:Female; D016368:Frameshift Mutation; D006801:Humans; D007438:Introns / Q000235:genetics; D008297:Male; D016884:Polyendocrinopathies, Autoimmune / Q000453:epidemiology / Q000235:genetics*; D015995:Prevalence; D022821:RNA Splice Sites / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D017524:Slovenia / Q000453:epidemiology; D014157:Transcription Factors / Q000235:genetics*; D000096927:AIRE Protein
D022821:RNA Splice Sites; D012333:RNA, Messenger; D014157:Transcription Factors; D000096927:AIRE Protein