Is lactose intolerance heredity?

Lactose intolerance: Lactose intolerance is common--25% of caucasians, 80% of afro-americans, almost 100% asians. Lactose intolerance can be secondary to lactase enzyme deficiency, or due to a bigger problem of small bowel inflammation, infection, infiltrative disease, and/or maldigestion. Don't assume its lactose intolerance unless tested, or at least assessed response to lactase enzyme replacement (like lactaid).