TY - JOUR
T1 - Diversity and function of mutations in P450 oxidoreductase in patients with Antley-Bixler syndrome and disordered steroidogenesis
AU - Huang, Ningwu
AU - Pandey, Amit V.
AU - Agrawal, Vishal
AU - Reardon, William
AU - Lapunzina, Pablo D.
AU - Mowat, David
AU - Jabs, Ethylin Wang
AU - Van Vliet, Guy
AU - Sack, Joseph
AU - Flück, Christa E.
AU - Miller, Walter L.
N1 - Funding Information:
This study is dedicated to the memory of Professor Robin M. Winter, who played a central role in associating FGFR mutations and craniosynostosis syndromes. This work was supported by the National Institutes of Health (NIH) Mentored Investigator Grant KO1 DK02939 (to N.H.) and by NIH grants RO1 DK37922, RO1 HD41958, and RO1 GM73020 (to W.L.M.). E.W.J. was supported by NIH grants P60 DE013078 and M01 RR00052. We thank Dr. Jacky Bonaventure and Dr. Martine LeMerrer (Hôpital Necker, Paris), Dr. Marie Gonzalez (Hôpital St. Antoine, Paris), and Dr. Kazuki Okajima (Case Western Reserve University, Cleveland), for contributing DNA samples and clinical information; Dr. Richard Kelly, for growing lymphoblastoid cell lines from several patients; Ms. Izabella Damm, for excellent technical assistance; and all the patients and families who participated in this study.
PY - 2005/5
Y1 - 2005/5
N2 - P450 oxidoreductase (POR) is the obligatory flavoprotein intermediate that transfers electrons from reduced nicotinamide adenine dinucleotide phosphate (NADPH) to all microsomal cytochrome P450 enzymes. Although mouse Por gene ablation causes embryonic lethality, POR missense mutations cause disordered steroidogenesis, ambiguous genitalia, and Antley-Bixler syndrome (ABS), which has also been attributed to fibroblast growth factor receptor 2 (FGFR2) mutations. We sequenced the POR gene and FGFR2 exons 8 and 10 in 32 individuals with ABS and/ or hormonal findings that suggested POR deficiency. POR and FGFR2 mutations segregated completely. Fifteen patients carried POR mutations on both alleles, 4 carried mutations on only one allele, 10 carried FGFR2 or FGFR3 mutations, and 3 patients carried no mutations. The 34 affected POR alleles included 10 with A287P (all from whites) and 7 with R457H (four Japanese, one African, two whites); 17 of the 34 alleles carried 16 "private" mutations, including 9 missense and 7 frameshift mutations. These 11 missense mutations, plus 10 others found in databases or reported elsewhere, were recreated by site-directed mutagenesis and were assessed by four assays: reduction of cytochrome c, oxidation of NADPH, support of 17α-hydroxylase activity, and support of 17,20 lyase using human P450c17. Assays that were based on cytochrome c, which is not a physiologic substrate for POR, correlated poorly with clinical phenotype, but assays that were based on POR's support of catalysis by P450c17 - the enzyme most closely associated with the hormonal phenotype - provided an excellent genotype/phenotype correlation. Our large survey of patients with ABS shows that individuals with an ABS-like phenotype and normal steroidogenesis have FGFR mutations, whereas those with ambiguous genitalia and disordered steroidogenesis should be recognized as having a distinct new disease: POR deficiency.
AB - P450 oxidoreductase (POR) is the obligatory flavoprotein intermediate that transfers electrons from reduced nicotinamide adenine dinucleotide phosphate (NADPH) to all microsomal cytochrome P450 enzymes. Although mouse Por gene ablation causes embryonic lethality, POR missense mutations cause disordered steroidogenesis, ambiguous genitalia, and Antley-Bixler syndrome (ABS), which has also been attributed to fibroblast growth factor receptor 2 (FGFR2) mutations. We sequenced the POR gene and FGFR2 exons 8 and 10 in 32 individuals with ABS and/ or hormonal findings that suggested POR deficiency. POR and FGFR2 mutations segregated completely. Fifteen patients carried POR mutations on both alleles, 4 carried mutations on only one allele, 10 carried FGFR2 or FGFR3 mutations, and 3 patients carried no mutations. The 34 affected POR alleles included 10 with A287P (all from whites) and 7 with R457H (four Japanese, one African, two whites); 17 of the 34 alleles carried 16 "private" mutations, including 9 missense and 7 frameshift mutations. These 11 missense mutations, plus 10 others found in databases or reported elsewhere, were recreated by site-directed mutagenesis and were assessed by four assays: reduction of cytochrome c, oxidation of NADPH, support of 17α-hydroxylase activity, and support of 17,20 lyase using human P450c17. Assays that were based on cytochrome c, which is not a physiologic substrate for POR, correlated poorly with clinical phenotype, but assays that were based on POR's support of catalysis by P450c17 - the enzyme most closely associated with the hormonal phenotype - provided an excellent genotype/phenotype correlation. Our large survey of patients with ABS shows that individuals with an ABS-like phenotype and normal steroidogenesis have FGFR mutations, whereas those with ambiguous genitalia and disordered steroidogenesis should be recognized as having a distinct new disease: POR deficiency.
UR - http://www.scopus.com/inward/record.url?scp=20244367932&partnerID=8YFLogxK
U2 - 10.1086/429417
DO - 10.1086/429417
M3 - Article
C2 - 15793702
AN - SCOPUS:20244367932
SN - 0002-9297
VL - 76
SP - 729
EP - 749
JO - American Journal of Human Genetics
JF - American Journal of Human Genetics
IS - 5
ER -