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Inthe questfora
cure, she says, “It’s amatter or patients | taking charge of their diagnosis.
to sequence his wife’s genomes. He paid several thou- sand dollars from his own pocket to learn his wife had calpainopathy.
The Topics had no such luxury. But they did have luck. Cornelius Boerkoel, a clinical geneticist at the University of British Columbia, enrolled the Topics in one of his studies, and so they didn’t have to pay to have each of the family member’s genomes sequenced. The genome tests gave Ivana and Antonia the bad news about calpainopathy. Their younger brother, Mario, is free of the disease.
Scientists classify calpainopathy, or “calpain,” as a limb-girdle muscular dystrophy Type 2a, caused by a mutation in the gene calpain 3, predominantly expressed in skeletal muscle. Those who suffer from Type 2a, such as Wrubel, Ivana, and Antonia, gener- ally exhibit weak hip flexors—muscles that lift up the thigh. The weak flexors give them an awkward gait; they swing their legs forward, landing on their toes, and then sometimes on the sides or soles of their feet. Some walk only on the balls of their feet. The upper body muscle weakness creates abnormally prominent shoulder blades.
Melissa Spencer from the University of California, Los Angeles, who has studied calpainopathy for 14 years, explains that the disease contains many sub- types. The problem with Type 2a, she says, “was a
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