title: High allele frequency of the p.Q258X mutation and identification of a novel mis-splicing mutation in the STAR gene in Korean patients with congenital lipoid adrenal hyperplasia.
abstract: OBJECTIVE
  Steroidogenic acute regulatory (STAR) protein plays a crucial role in steroidogenesis, and mutations in the STAR gene cause congenital lipoid adrenal hyperplasia (CLAH). This study investigated the STAR mutation spectrum and functionally analyzed a novel STAR mutation in Korean patients with CLAH.
  
  
  METHODS
  Mutation analysis of STAR was carried out in 25 unrelated Korean CLAH patients. A region of STAR comprising exons 4-7 was cloned from human genomic DNA into an expression vector, followed by site-directed mutagenesis and transient expression in COS7 cells. The splicing pattern was analyzed by in vitro transcription, and each transcript was functionally characterized by measuring pregnenolone production in COS7 cells cotransfected with the cholesterol side chain cleavage system.
  
  
  RESULTS
  Mutation p.Q258X was identified in 46 of 50 alleles (92%); mutation c.653C>T was detected in two alleles (4%); and mutations p.R182H and c.745-6_810del were found in one allele (2%). Reverse transcriptase-PCR products amplified from a patient heterozygous for compound c.653C>T and c.745-6_810del mutation revealed multiple alternatively spliced mRNAs. In vitro expression analysis of a minigene consisting of exons 4-7 containing the c.653C>T yielded two transcripts in which exon 6 or exons 5 and 6 were skipped. The encoded proteins exhibited defective pregnenolone-producing ability. The c.745-6_810del mutation led to full and partial intron retention.
  
  
  CONCLUSIONS
  p.Q258X is the most common STAR mutation in Korea. A previously reported c.653C>T variant was found to cause aberrant splicing at the mRNA level, resulting in perturbation of STAR function. The c.745-6_810del mutation also resulted in aberrant splicing.
authors.affiliation: Division of Pediatric Endocrinology and Metabolism, Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, 388-1, Pungnap-Dong, Songpa-Gu, Seoul 138-736, Republic of Korea.
authors.forename: Jae-Min
authors.initials: JM
authors.lastname: Kim
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Choi
authors.forename: Jung Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Gu-Hwan
authors.initials: GH
authors.lastname: Kim
authors.forename: Beom Hee
authors.initials: BH
authors.lastname: Lee
authors.forename: Hae Soon
authors.initials: HS
authors.lastname: Kim
authors.forename: Jeh-Hoon
authors.initials: JH
authors.lastname: Shin
authors.forename: Choong-Ho
authors.initials: CH
authors.lastname: Shin
authors.forename: Chan Jong
authors.initials: CJ
authors.lastname: Kim
authors.forename: Jeesuk
authors.initials: J
authors.lastname: Yu
authors.forename: Dae-Yeol
authors.initials: DY
authors.lastname: Lee
authors.forename: Won Kyoung
authors.initials: WK
authors.lastname: Cho
authors.forename: Byung-Kyu
authors.initials: BK
authors.lastname: Suh
authors.forename: Ji Eun
authors.initials: JE
authors.lastname: Lee
authors.forename: Hye Rim
authors.initials: HR
authors.lastname: Chung
authors.forename: Han-Wook
authors.initials: HW
authors.lastname: Yoo
mesh_terms: D000293:Adolescent; D000312:Adrenal Hyperplasia, Congenital / Q000453:epidemiology / Q000235:genetics*; D017398:Alternative Splicing / Q000235:genetics*; D000818:Animals; D044466:Asian People / Q000235:genetics*; D019556:COS Cells; D002648:Child; D002675:Child, Preschool; D002522:Chlorocebus aethiops; D058490:Disorder of Sex Development, 46,XY / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D005787:Gene Frequency / Q000235:genetics*; D006801:Humans; D007223:Infant; D007723:Korea / Q000453:epidemiology; D008297:Male; D009154:Mutation / Q000235:genetics*; D010750:Phosphoproteins / Q000235:genetics*; D000098682:Steroidogenic Acute Regulatory Protein
chemical_list: D010750:Phosphoproteins; D000098682:Steroidogenic Acute Regulatory Protein