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Hum Genet. 1998 May;102(5):571-5.

Partial biotinidase deficiency is usually due to the D444H mutation in the biotinidase gene.

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Department of Human Genetics, Medical College of Virginia at Virginia Commonwealth University, Richmond 23298, USA.

Erratum in

  • Hum Genet 1998 Jun;102(6):712.


Newborn screening for biotinidase deficiency has identified children with profound biotinidase deficiency (<10% of mean normal serum activity) and those with partial biotinidase deficiency (10%-30% of mean normal serum activity). Children with partial biotinidase deficiency and who are not treated with biotin do not usually exhibit symptoms unless they are stressed (i.e., prolonged infection). We found that 18 of 19 randomly selected individuals with partial deficiency have the transversion missense mutation G1330>C, which substitutes a histidine for aspartic acid444 (D444H) in one allele of the biotinidase gene. We have previously estimated that the D444H mutation results in 48% of normal enzyme activity for that allele and occurs with an estimated frequency of 0.039 in the general population. The D444H mutation in biotinidase deficiency is similar to the Duarte variant in galactosemia. The D444H mutation in one allele in combination with a mutation for profound deficiency in the other allele is the common cause of partial biotinidase deficiency.

[Indexed for MEDLINE]

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