title: Development of a new enzymatic diagnosis method for very-long-chain Acyl-CoA dehydrogenase deficiency by detecting 2-hexadecenoyl-CoA production and its application in tandem mass spectrometry-based selective screening and newborn screening in Japan.
abstract: The introduction of tandem mass spectrometry (MS/MS) has made it possible to screen for very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency. To confirm the diagnosis in cases with an abnormal profile of blood acylcarnitines, we developed a new enzymatic assay method for determining dehydrogenase activity toward palmitoyl-CoA (C16:0) in lymphocytes. Using this method, the production of 2-hexadecenoyl-CoA (C16:1) by crude cell lysates can be directly quantified using high performance liquid chromatography (HPLC). We applied the assay to 7 myopathic patients, 7 hypoglycemic patients, and 2 presymptomatic newborns with elevated levels of tetradecenoylcarnitine (C14:1 AC) in blood, and found impaired VLCAD activity in all of the 7 myopathic patients and both of the 2 newborns. All of the 7 hypoglycemic patients had normal level of the enzyme activity. Results of the ACADVL gene analysis were in consistent with the enzymatic diagnosis. These results suggest that MS/MS-based screening for VLCAD deficiency using blood C14:1 AC as the indicator may show a considerably high false-positive rate in selective screening of symptomatic patients. Our practical enzymatic assay can be a useful test for the accurate diagnosis of VLCAD deficiency cases screened by MS/MS.
authors.affiliation: Department of Pediatrics, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima 734-8551, Japan. acadugo@mac.com
authors.forename: Go
authors.initials: G
authors.lastname: Tajima
authors.forename: Nobuo
authors.initials: N
authors.lastname: Sakura
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Shirao
authors.forename: Satoshi
authors.initials: S
authors.lastname: Okada
authors.forename: Miyuki
authors.initials: M
authors.lastname: Tsumura
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ono
authors.forename: Yuki
authors.initials: Y
authors.lastname: Hasegawa
authors.forename: Ikue
authors.initials: I
authors.lastname: Hata
authors.forename: Etsuo
authors.initials: E
authors.lastname: Naito
authors.forename: Seiji
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Shigematsu
authors.forename: Masao
authors.initials: M
authors.lastname: Kobayashi
mesh_terms: D000214:Acyl Coenzyme A / Q000378:metabolism*; D044942:Acyl-CoA Dehydrogenase, Long-Chain / Q000172:deficiency* / Q000235:genetics; D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007564:Japan; D052439:Lipid Metabolism Disorders / Q000175:diagnosis* / Q000235:genetics; D008297:Male; D015997:Neonatal Screening / Q000379:methods*; D010171:Palmitoyl Coenzyme A / Q000378:metabolism; D053719:Tandem Mass Spectrometry / Q000379:methods*; D055815:Young Adult
chemical_list: C117110:2-hexadecenoyl-coenzyme A; D000214:Acyl Coenzyme A; D010171:Palmitoyl Coenzyme A; D044942:Acyl-CoA Dehydrogenase, Long-Chain