22q11.2 deletion syndrome is caused by the deletion of a small section of chromosome 22. It results in a cleft palate, heart defects, autoimmune disorders, and more. The symptoms vary wildly and can be accompanied by learning disabilities and mental illness. Cystic fibrosis is caused by a point deletion.
The melody of Happy Birthday to You comes from the song  Good Morning to All , which has been attributed to American siblings Patty Hill and Mildred J. Hill in 1893, although the claim that the sisters composed the tune is disputed.
Oh Happy Day  is a 1967 gospel music arrangement of an 18th-century hymn. Recorded by the Edwin Hawkins Singers, it became an international hit in 1969, reaching No. 4 in the US and No. 2 in both the UK singles chart and Irish Singles Chart. It has since become a gospel music standard.