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Week 32/2009: A gene test to detect lactose intolerance

When diagnosing lactose intolerance, a gene test would be more practical than the lactose tolerance test currently in use. This finding was reported in a dissertation to be examined at the University of Helsinki.

Patients experiencing stomach problems should also be tested for celiac disease. Nearly one per cent of subjects participating in the study by Sari Anthoni, Head of Occupational Health Care, were found to suffer from undetected celiac disease.

When combined with cases with a previous diagnosis, an approximate total of two per cent suffered from celiac disease. This is a significant result, as the frequency of the disorder in the general population is estimated to be one per cent at most.
In her dissertation, Anthoni studied milk-related stomach problems in adult patients using a sample of 1,900 health centre clients in the Helsinki metropolitan area.

All test subjects filled out a questionnaire on food and milk-related ailments, and gave a blood sample.
40 per cent of the participants suspected milk to be the cause of their stomach problems. 62 per cent connected their ailments to food in general, Anthoni says.

80 per cent of the participants had suffered from stomach ailments in the last three months. Anthoni does, however, believe it possible that people who had experienced problems were particularly inclined to participate in the study.

For people who drink milk, stomach ailments are most frequently caused by the insufficient operation of the lactase enzyme in the intestines, resulting in poor metabolisation of milk sugar, or lactose. The poor lactase operation is connected to certain genes that can be detected by modern testing techniques. Anthoni believes that traditional lactose tolerance tests should be replaced by gene testing.

Tolerance tests yield a relatively high count of false results. They are also more expensive than gene tests. In addition to tests, a milk-free diet is in order when diagnosing milk-related stomach symptoms. According to the study, celiac disease can be reliably ruled out by checking the transglutaminase or endomysial antibodies from a blood sample.

According to the results, the IgE antibodies and the related IgA and IgG antibodies often found in connection with children’s stomach ailments did not correlate with stomach ailments in adults. Therefore, they need not be examined in adults.

Text: Mikko Puttonen
Picture: Maito ja terveys ry
Translation: AAC Noodi

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