CRISPR

For Taina Maitre, sickle cell disease has meant frequent pain and missed opportunities. Last winter, she was in the hospital for Thanksgiving. And for Christmas. And again, for New Years.

When Elenoe “Crew” Smith first learned about sickle cell disease, it was part of a seventh-grade genetics lesson on passing traits — alongside the height and color of Mendel’s pea plants — from one generation to the next.

The treatments, both produced by Boston-area companies, join 32 other approved gene therapies and are approved to treat the disease in the United States.