Neonatal hypertyrosinemia and evidence for deficiency of ascorbic acid in Arctic and subarctic peoples
Clow, C.L.; Laberge, C.; Scriver, C.R.
Canadian Medical Association Journal 113(7): 624-626
1975
ISSN/ISBN: 0008-4409 PMID: 1181017 Document Number: 90181
Hypertyrosinaemia (concentrations in whole blood >7.5 mg/100 ml) was found in 14.8% of newborn Inuit in the Canadian eastern Arctic and subarctic region from January 1970 to December 1972, and in 6.2% from January 1973 to September 1974. Corresponding rates among Indian newborn in northern Quebec were 2.6 and 2.2%. In a group of French Canadian newborn in an urban community in southern Quebec the incidence was 1.4% and in an Anglo-Saxon group in Montreal 0.41%. In 1970-72 Nutrition Canada found low serum concentrations of ascorbic acid ( less than or equal to 0.25 mg/100ml) in age-matched and pregnant adult Inuit; 14.8% of Inuit children up to 4 years old and 47.1% of pregnant women had <0.2 mg/100 ml, compared with national values of 3.0 and 2.2%. Deficiency of ascorbic acid among pregnant Inuit women is suggested as the probable cause of the unusual prevalence of hypertyrosinaemia among the newborn. Nutrition Canada values show that average intakes of ascorbic acid by the samples of pregnant women among the Inuit and Indians and in Quebec province and all Canada were, respectively, 28, 62, 130 and 133 mg/day.