Sir Tom Jones is planning to get a DNA test to discover whether he has any ''black blood'' after his mother developed ''big dark patches'' over her skin when she gave birth to him. The 75-year-old singer has admitted he's always wondered if he's mixed race because of his olive skin and afro-style bright white hair, and is keen to get a test done in the near future to gain a better understanding of his background.He explained to The Times magazine: "A lot of people still think I'm black. When I first came to America, people who had heard me sing on the radio would be surprised that I was white when they saw me. Because of my hair, a lot of black people still tell me that I'm just passing as white."The Sex Bomb hitmaker is keen to explore the ancestors of his mother Freda, who was of Welsh and English descent, after she puzzled doctors when she developed "big dark patches" over her skin when she gave birth to Tom. The star, who was born in Pontypridd, South Wales, added: "When I was born, my mother came out in big dark patches all over her body. They [the doctors and midwives] asked if she had any black blood and she said she didn't know. I'm going to get my DNA tested. I want to find out."..