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Comment
. 2003 May;52(5):617-9.
doi: 10.1136/gut.52.5.617.

Changing genes; losing lactase

R J Grand  1 , R K Montgomery, D K Chitkara, J N Hirschhorn
Affiliations
Comment

Changing genes; losing lactase

R J Grand et al. Gut. 2003 May.
No abstract available

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Figures

Figure 1
Figure 1
Model of the molecular forms of lactase-phlorizin hydrolase during synthesis and processing in the human villus enterocyte. The early changes in apparent molecular size are due to glycosylation, as indicated in the diagram. Note that the two active sites are located in domains III and IV. The subsequently removed domains I and II are important for correct folding of the nascent protein. Although not indicated on this drawing, the enzyme forms a homodimer during processing. The final N terminal cleavage of a small segment is depicted by the elimination of the terminal loop in the microvillus form of the enzyme.
Figure 2
Figure 2
Schematic representation of the region between the two highlighted genetic markers that is associated with adult-type hypolactasia (Enattah and colleagues20). Vertical bars within the MCM6 gene represent the exons, the widths indicating relative size. The two associated single base polymorphisms (SNPs) lie within the indicated introns of the MCM6 gene which is located 5′ to the LCT (lactase-phlorizin hydrolase) gene on human chromosome 2. The arrows indicate the direction of gene transcription (the centromeric region of the chromosome is located to the left). The scale bar at the bottom of the figure indicates the size of the DNA region occupied by the MCM6 gene. The numbers at introns 13 and 9 indicate the positions of the SNPs relative to the transcriptional start site of lactase (redrawn from Enattah and colleagues20).
See this image and copyright information in PMC

Comment on

References

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