BBC Friday, 3 August, 2001, 23:11 GMT 00:11 UK Gene warning over HIV drug Aids drugs: How will they work in Africa?

West Africans may have a genetic makeup which could prevent some anti-HIV drugs working properly, say scientists.

Commonly-used drugs such as protease inhibitors could be affected, the research team - from Stuttgart in Germany - say in a letter to the Lancet medical journal.

The discovery comes as the debate continues over the availability of such drugs in developing countries.

Researchers looked at the genetic makeups of 172 Ghanaians, 41 African/Americans, 40 Japanese and 537 white people.

They found that the vast majority - approximately 80% - of the Ghanaians tested positive for a gene type they called C/C.

Only just over one in five of the white people tested had that genotype.

The C/C genotype was linked to a much higher concentration of a particular protein in the cells which line the gut.

The anti-retroviral drugs in question are quite similar to this protein.

This means that it might be difficult for the drug proteins to find vacant receptors on the cells they need to target for the medication to work.

Quite why west Africans, and to a lesser extent, African Americans are more likely to have the gene type is not known.

Gut advantage

However, the research team suggests that the difference might naturally give these populations an advantage when it comes to fighting gastro-intestinal infections.

However, the Terrence Higgins Trust Lighthouse, the UK HIV/Aids charity, said that the finding should not influence any arguments over the availability of anti-retrovirals in Africa and elsewhere in the developing world.

A spokesman said: "It should be remembered that there are a wide variety of combinations of drugs available.

"If one combination does not work, there is likely to be another which is more effective.

"Everybody responds differently to treatment."

The leaders of the world's most highly-developed countries recently promised a $1bn fund to help fight Aids, malaria and TB.

Despite this, many politicians and drug-makers are still sceptical whether complex combinations of potentially dangerous drugs can be adequately supervised and monitored in isolated communities.

However, a separate paper in the Lancet provides encouragement for those who believe it can be done.

A research project in Haiti used the same methods as those employed in the fight against TB.

To ensure compliance, patients actually had to take the pills in the presence of a doctor or nurse.

The researchers wrote that if the treatments could be introduced in the central plains of Haiti, they could be introduced anywhere.

-- Anonymous, August 03, 2001