Diagnostic patterns of very-long-chain fatty acids in plasma of patients with X-linked adrenoleukodystrophy

Pattern recognition analysis on the levels of the very-long-chain fatty aci ds (VLCFAs) in plasma is described for the visual discrimination of X-linke d adrenoleukodystrophy (X-ALD) patients from normal healthy group. Plasma V LCFA compositions of 58 normal subjects and 16 X-ALD patients were examined by gas chromatography as their methyl esters to determine the area percent ages of behenic acid (C22:0), lignoceric acid (C24:0) and hexacosanoic acid (C26:0) in the total fatty acids, and the concentration (mug/ml) of C26:0. When star symbol plotting was applied to the VLCFA values of C22:0 (%), C2 4:0 (%), C26:0 (%), C24:0/C22:0, C26:0/C22:0 and C26:0 (mug/ml) after norma lization to the corresponding median values in normal group, the resulting deformed hexagonal star pattern was characteristic of each patient. Therefo re, simple visual comparison with the equilateral hexagon of normal group a verage as the control pattern enabled one readily to discriminate X-ALD pat ients from the normal group. Additionally, canonical discriminant analysis performed on the six unnormalized VLCFA values correctly classified 74 plas ma specimens into two separate clusters according to normal subject or X-AL D patient in the canonical plot. (C) 2001 Elsevier Science B.V. All rights reserved.