He had his secondary education at the Accra Academy from 1970 to 1972, and King Edward VII School, Sheffield from 1973 to 1975.
He then continued at the University of California, Berkeley for a post doctoral research in Molecular Evolution under the supervision of Evolutionary Biologist, Allan Wilson from 1983 to 1984.
[1][3] McClelland taught Chemistry and Biology at Beveweerd School prior to entering the University of Georgia for his postgraduate studies.
[3][8][9][10][11][12] He worked in this capacity until 1995 when he was appointed Professor and Director of Genomics and Bioinformatics at the Sidney Kimmel Cancer Center, San Diego, California.
He was the Chairman of Novel Technologies RFA Study Section, and an external reviewer for the Department of Education (UK).