Needroots on Family Tree Circles

I was born Michael A. Walker in Columbus, Ohio in 1953. I was born in the Friends Rescue Mission. I am desparately trying to locate my birth family. My birth mother's name is Alberta Elaine Walker. I have one older brother whose name I do not know. I only want ETHNIC HISTORY and MEDICAL HISTORY. I have NO desire to intrude otherwise on these people's lives. PLEASE HELP!