The Editor, Sir:

Dr Pauline Williams-Green is to be congratulated on drawing attention to the importance of knowing your 'sickle status' (Gleaner, September 9). In fact, one could broaden this recommendation to knowing one's haemoglobin genotype, since this refers to the common genes (HbS, HbC, beta thalassaemia) which put one at risk of having a child affected by sickle-cell disease. These genes occur in 15 per cent of Jamaicans, so more than 400,000 Jamaicans are at risk of having an affected child.

Whether you have an affected child depends on your choice of partner, since if one parent is absolutely normal, you cannot have a child with the disease. So, with this information, sickle-cell disease could be prevented. This has already been achieved in Bahrain where premarital screening for the sickle-cell gene has halved the frequency of affected births.

Carrier status

Now the challenge must be to see whether informing people of their carrier status at younger ages will 'empower' them to select partners who will avoid an affected child. In Manchester, a study has been under way for two years, offering detection of these haemoglobin genes to the senior school children of the 15 secondary schools in the parish. They are given permanent laminated cards with their genotype and counselling is given to the identified carriers. To see whether this information will decrease the affected births, newborn screening has been set up in the three maternity units in the parish.

Affected children

This project is funded for the next five years by the National Health Fund and the Alcoa Foundation. Everyone has a right to know his or her haemoglobin genotype and so be empowered to avoid having affected children. In sub-Saharan Africa where 250,000 babies with severe forms of sickle-cell disease are born each year, prevention is the only hope of reducing the scale of this burden so that the limited resources may be used for more effective treatment of the remaining patients. Hopefully, the Manchester project will provide the Jamaican and other governments with a model for prevention of this disease, which will not only prevent much personal distress but also save resources for the health services. More can be learnt on the Manchester project from the Sickle Cell Trust (Jamaica), 970 0077, or from the web site, sicklecelltrustjamaica.com.

I am, etc.,

GRAHAM SERJEANT

Kingston 6