tool geneticists

Until recently,
the only tool geneticists had in the search for genes was the observation of
patterns of inheritance (like those shown in Chapter 12) and the subsequent
comparisons of how various groups of traits were inherited. This method,
called linkage analysis, is used to construct gene maps (see Chapter 4).
With the advent of DNA sequencing (see Chapter 11), however, the search
for names and addresses of genes has reached a whole new level (but the
search still isn’t over; see the sidebar “The role of the Human Genome
Project”).