A recount of genes

How many genes, after all, does man have? During the last few years, the calculation indicated that it could be between 64,000 and 120,000. However, according to studies released in May in the magazine Nature Genetics, the total may now vary between 30,000 and 34,000 genes. The answer is still not conclusive. Another piece of research, in the same publication, suggests that human DNA will really be made up of 120,000 genes. The differences can be accounted for probably by the technique applied, based on the fragments of DNA called ESTs (Expressed Sequence Tags). It was thought that there was a direct relationship between the number of ESTs and that of the genes. It might not be so as evidence has been accumulating that a single gene can originate more than one EST.