Unimodular lattices and strongly regular graphs

New connections are found between unimodular even lattices and strongly regular graphs. Two cases are considered: the case of lattices of dimension 32 with root sistem of type $A_1$ and the case of extremal lattice of dimension $48$. In both cases strongly regular graphs are constructed from a given lattice. In the first case these graphs have the same parameters as the graphs arising from some Steiner geomerties.