Develop a musical composition by integrating the alphabetically represented musical pattern and the supplied melodic theme.
X:1
L:1/8
M:4/4
K:G
['GDGA B2 B2 AGAB c2 c2 GABc', 'gdde/f/ gddc']  
X:1
L:1/8
M:4/4
K:G
 GDGA B2 B2 | AGAB c2 c2 | GABc dedB | BGdB G2 G2 :: gdde/f/ gddc | BGAB c2 c2 | gdde/f/ gddc | 
 BGdB G2 G2 :|  