RNAi therapeutics firm Alnylam Pharmaceuticals and consumer genetics firm 23andMe will offer free genetic test kits to first-degree family members of 23andMe customers who have a TTR variant known to cause hereditary amyloidosis.

Hereditary ATTR amyloidosis (hATTR) is caused by a build up of the transthyretin protein that can damage tissues and organs. The condition is inherited but is rare and hard to diagnose. Late diagnosis can result in poor patient outcomes.

Since 2017, Alnylam has partnered with genetic testing firm Invitae on a free genetic testing service called Alnylam Act that aims to facilitate early testing and diagnosis for hATTR, as well as other rare conditions. Within this program, Invitae provides sequencing that it says identifies more than 99 percent of pathogenic variants in TTR.  

23andMe's test report, which it launched in April this year, tells customers if they harbor three common TTR variants — V122I, V30M, and T60A — that comprise between 50 percent and 80 percent of hATTR cases, but not all variants linked to the condition. The introduction of the new test report was partly supported by Alnylam.

"hATTR amyloidosis is a devastating condition that affects families, generation after generation," Alnylam CEO John Maraganore, said in a statement. "This unique collaboration with 23andMe builds on our commitment to raising awareness and providing education about this rare disease, which people often struggle with for years until receiving a proper diagnosis."

The free family testing program builds on the companies' earlier collaboration related to this condition. 23andMe customers who learn they have one of the three TTR variants and have opted to partake in research can invite as many as six first-degree relatives to receive a free health and ancestry kit.

It will then be up to the family members to decide with they want to view the TTR variant report. Within this program, 23andMe will not share identifiable data with Alnylam.