Rat Argininosuccinate Lyase, ASL ELI

American Sign Language (ASL) is a natural language that serves as the predominant sign language of Deaf communities in the United States and most of Anglophone Canada.

ASL is a complete and organized visual language that is expressed by facial expression as well as movements and motions with the hands.

Besides North America, dialects of ASL and ASL-based creoles are used in many countries around the world, including much of West Africa and parts of Southeast Asia.

ASL is also widely learned as a second language, serving as a lingua franca.

ASL is most closely related to French Sign Language (LSF).

It has been proposed that ASL is a creole language of LSF, although ASL shows features atypical of creole languages, such as agglutinative morphology.