Contreras RJ, Alonso JE, Evelyn FL, Gandarilla A

Language: Spanish
References: 13
Page: 26-30
PDF size: 575.94 Kb.

ABSTRACT

Hyperphenylalaninemias are a group of inborn metabolism errors of the phenylalanine amino acid, due to deficiencies in the conversion of phenylalanine into tyrosine, specifically related to the phenylalanine hydroxylation by the phenylalanine hydroxylase enzyme. From the biochemical point of view, this alteration produces a phenylalanine concentration in serum (› 4 mg/dL or 240 µM) and from the clinical point of view it is fundamentally characterized by severe mental handicap. In the National Center of Medical Genetics this disease is diagnosed and classified by means of the fluorometric determination of phenylalanine in serum. Since the phenylalanine/tyrosine ratio is widely reported as the second diagnosis criterion for hyperphenylalaninemias, a high-resolution liquid chromatography method was validated allowing the simultaneous quantification of phenylalanine and tyrosine in serum. In this paper, results of the quantification of both amino acids in healthy and hyperphenylalaninemia Cuban children are being reported aimed at the determination of the phenylalanine/tyrosine ratio in both groups studied.

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