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:C
['GEcA GECE GEcA G2 z2 GEcA GAcd', 'cdef gage']  
X:1
L:1/8
M:4/4
K:C
 GEcA GECE | GEcA G2 z2 | GEcA GAcd | edcA d2 cA :| cdef gage | gage f2 ed | cdef gage | 
 agec d2 cA :|  