Asian clan

The Tōyō no ichizoku (東洋の一族) is a bloodline within the walls originating from a land called Asia.

History
When the First King erased humanity's memories shortly after the creation of the walls, the Asian bloodline was one of the minority groups unaffected by the mindwipe due to not sharing the bloodline of the majority race of the walls. After turning against the Royal Government alongside the Ackerman family and rejecting the First King's offer of nobility, the Asian bloodline was exiled from society and hunted down. By the year 844, it was said that the Asian bloodline had been hunted down to near extinction within the walls.

Battle of Trost District arc
During the Battle of Trost District, Mikasa Ackerman recalls the time from her childhood when her mother and father were killed by human traffickers who were hoping to sell her and her mother to potential buyers in Mitras. She is rescued by Eren Yeager, killing two of the traffickers before Mikasa kills the third with her awakened Ackerman abilities. After the death of her mother, Mikasa Ackerman becomes the last surviving member of the Asian bloodline known to exist within the walls.

The Uprising arc
In a conversation with Levi Ackerman before their confrontation with Kenny Ackerman and his subordinates, Mikasa mentions how her mother's family lost their home, possibly due to their Asian heritage.

Trivia

 * In the manga, the Asian family possesses a special tattoo-like brand passed down from generation to generation, which Mikasa receives from her mother shortly before her parents are murdered. In the anime and the visual novel, this brand is replaced with a unique stitching method.
 * Due to the etymology of Mikasa's name, it is very likely that the Asian bloodline originated from the Japanese islands of East Asia. However, it has also been stated by Hajime Isayama that the "East Sea" in the Attack on Titan world differs in some way from the East Asian region in the real world, though this difference has not yet been explained.
 * So far, the Asian clan has only been credited with immunity to Memory Manipulation.