Article

Prevalence of adult-type hypolactasia as diagnosed with genetic and lactose hydrogen breath tests in Hungarians.

Institute of Genetics, Biological Research Centre of Hungarian Academy of Sciences, POB 521, Szeged H-6701, Hungary.
European journal of clinical nutrition (impact factor: 3.07). 02/2009; 63(7):909-12. DOI:10.1038/ejcn.2008.74 pp.909-12
Source: PubMed

ABSTRACT The prevalence of adult-type hypolactasia varies ethnically and geographically among populations. A C/T(-13910) single nucleotide polymorphism (SNP), upstream of the lactase gene, is known to be associated with lactase non-persistence. The aim of this study was to determine the prevalence of lactase-persistent and non-persistent genotypes in the Hungarian population, the age at onset and the applicability of the lactose H2 breath test in comparison with genetic screening. The prevalence of the C/C(-13910) genotype among adults was 37%. Hypolactasia starts to appear at around 5 years of age. Over the age of 12 years, almost all of those with a C/C(-13910) genotype have lactase non-persistence. The C/C(-13910) genotype was closely associated with a positive lactose H2 breath test in symptomatic children, whereas the lactase-persistent genotypes correlated better with a negative H2 test in a control group. In conclusion, supplementary non-invasive breath and genotyping tests furnish a perfect clinical diagnosis.

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    BMC Evolutionary Biology 02/2010; 10:36. · 3.52 Impact Factor
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Keywords

adult-type hypolactasia varies
 
control group
 
genetic screening
 
genotyping tests furnish
 
Hypolactasia
 
lactase-persistent
 
lactase-persistent genotypes correlated
 
lactose H2 breath test
 
negative H2 test
 
non-persistent genotypes
 
positive lactose H2 breath test
 
prevalence
 
SNP
 
symptomatic children