The index, which underperformed the Dow Jones and the Nasdaq, gave back the 11 percent gain it made in June.
Financial analysts seemed convinced of the long-term advantages of the deal but noted that investors may remain skeptical in the near term.
The company's total revenues were $114.1 million compared with $95.6 million in the same quarter last year, beating analysts' expectations.
Exact said it will pay $72 per share for Genomic Health for a total transaction price of $2.8 billion in cash and stock.
Invitae said this week that it completed its acquisition of Singular Bio on June 19.
Exact Sciences and the Mayo Clinic are working to develop a blood test for pancreatic cancer that might be able to diagnose patients with early-stage disease.
The FLASH method, which depletes unwanted DNA from samples, allows labs to perform deep metagenomic sequencing on smaller, less expensive instruments.
During its earnings call this week, the liquid biopsy firm said it is planning a 10,000-patient trial to test its Lunar assay for colorectal cancer screening.
The index, which underperformed the Dow Jones and the Nasdaq, fell nearly 3 percent in April.
The firm recently submitted an application to the US Food and Drug Administration to expand Cologuard's label to the 45 to 49 age group.
The Wall Street Journal looks into FamilyTreeDNA's handling of genetic genealogy searches by law enforcement.
In a point-counterpoint in the Boston Globe, researchers discuss the potential of gene editing to prevent Lyme disease, but also the pitfalls of doing so.
MIT's Technology Review reports that researchers hope to develop a CRISPR-based pain therapy.
In Science this week: atlas of malaria parasites' gene expression across their life cycles, and more.