This is the silver lining of the worsening doctor shortage – the opportunity to replace a wave of retiring physicians with a new generation of culturally attuned young professionals. In California, with its many underserved ethnic populations, the need for a multicultural health care workforce will be particularly great, as uninsured people sign up for health care coverage under the Affordable Care Act, experts say. The surge of new patients will come as the California Academy of Family Physicians expects 30 percent of primary care doctors to retire in the next few years. The organization runs a program called Future Faces of Family Medicine, aiming to recruit low-income and ethnic minority youths into the medical profession.