It is now possible to get the GERP constrained elements via the DAS protocol. For instance the DAS command to get all the GERP elements on the BRCA2 gene (Human chr 13: 32889611-32973347) is:
http://www.ensembl.org/das/Homo_sapiens.GRCh37.constrained_element/features?segment=13:32889611,32973347
By default, you obtain both the constrained derived from our 16-way amniote alignments and the 33-way placental mammals ones (these include all the low-coverage genomes). You can filter the elements you want by using the argument type:
http://www.ensembl.org/das/Homo_sapiens.GRCh37.constrained_element/features?segment=13:32889611,32973347;type=33_eutherian_mammals
Read more on DAS or on the multiple alignments and constrained elements.

What is GERP?
GERP is a method to detect conserved regions. It requires a genomic multiple alignment. See:
http://mendel.stanford.edu/SidowLab/downloads/gerp/