Human Genome Research Project

Biochemical Genetics and Newborn Screening

• Head of Unit
• Research Aspect One - Evaluation of the use of tandem mass-spectrometry (MSMS) in newborn screening
• Research Aspect Two - Studies in vitamin B12 deficiency

See also: Biochemical Genetics, NSW Biochemical Genetics Service and Newborn Screening in hospital's Directory of Services.

Head of Unit

Research Aspect One - Evaluation of the use of tandem mass-spectrometry (MSMS) in newborn screening

MSMS is used for the detection of disorders of amino acid, organic acid and fatty acid metabolism in the newborn. Because of the extreme rarity of most individual disorders and the long-term follow-up needed, an approach using a randomised controlled trial in evaluation is not feasible. With NH&MRC funding we initiated an Australia-wide study of the outcome of screening, with approximately 2 million babies born between April 1994 and March 2002, 560,000 screened, and the remainder forming two control cohorts, historical and contemporaneous. We found that more patients with fatty acid oxidation defects were detected by screening, mainly affecting medium-chain Acyl-CoA dehydrogenase (MCAD) deficiency. Preliminary findings indicate modest clinical benefits, reduced costs, and avoidance of a few deaths. Leigh Waddell studied mutations in the MCAD patients, finding a different profile than that reported in clinically.

Research Aspect Two - Studies in vitamin B12 deficiency

Kath Green has developed small volume, inexpensive assays of plasma methylmalonic acid and homocysteine using MSMS, to indicate B12 deficiency, and has found that a significant proportion of adults with inborn errors of metabolism on low protein diets have low or marginal B12 levels.