The small community of the genetically rare

Too readily lumped into autism, technology is teasing out those with deletions or duplications in their DNA.

Few of these mutations were inherited in the traditional sense, and the affected children are typically the only family member with the disorder. So, many parents are searching out strangers struck by the same genetic lightning bolt... Sometimes what they find is unsettling. But in the emerging communities of the genetically rare, more often it is sustaining.