The molecular basis of lactose intolerance
Campbell AK, Waud JP, Matthews SB.
Department of Medical Biochemistry and Immunology,
Wales College of Medicine,
Cardiff University,
Cardiff CF14 XN, UK.
Sci Prog. 2005;88(Pt 3):157-202.


A staggering 4000 million people cannot digest lactose, the sugar in milk, properly. All mammals, apart from white Northern Europeans and few tribes in Africa and Asia, lose most of their lactase, the enzyme that cleaves lactose into galactose and glucose, after weaning. Lactose intolerance causes gut and a range of systemic symptoms, though the threshold to lactose varies considerably between ethnic groups and individuals within a group. The molecular basis of inherited hypolactasia has yet to be identified, though two polymorphisms in the introns of a helicase upstream from the lactase gene correlate closely with hypolactasia, and thus lactose intolerance. The symptoms of lactose intolerance are caused by gases and toxins produced by anaerobic bacteria in the large intestine. Bacterial toxins may play a key role in several other diseases, such as diabetes, rheumatoid arthritis, multiple sclerosis and some cancers. The problem of lactose intolerance has been exacerbated because of the addition of products containing lactose to various foods and drinks without being on the label. Lactose intolerance fits exactly the illness that Charles Darwin suffered from for over 40 years, and yet was never diagnosed. Darwin missed something else--the key to our own evolution--the Rubicon some 300 million years ago that produced lactose and lactase in sufficient amounts to be susceptible to natural selection.
Women's Rights
Julian Savulescu
Private eugenics
'Designer babies'
Procreative liberty
Personal genomics
Genetic enhancement
Ashkenazi intelligence
Eugenics before Galton
Scandanavian eugenics
The literature of eugenics
Human self-domestication
Germline genetic engineering
Preimplantation genetic diagnosis
Beneficence, determinism and justice
A life without pain? Hedonists take note'
'The Principle of Procreative Beneficence'

and further reading

BLTC Research
Utopian Surgery?
The Good Drug Guide
The Abolitionist Project
The Hedonistic Imperative
The Reproductive Revolution
MDMA: Utopian Pharmacology
Critique of Huxley's Brave New World