Develop a musical composition by integrating the alphabetically represented musical pattern and the supplied melodic theme.
X:1
L:1/8
M:2/2
K:G
['AG G2', 'dg g2']  
X:1
L:1/8
M:2/2
K:G
 AG G2 AGFD | AG G2 Addc | AG G2 AGFD | =FEFG ABcA :| dg g2 aggf | dgge fdcA | dg g2 aggf | 
 d^cde fd=cA | dg g2 ag (3efg | abag f3 g | af (3gfe fde^c | dfeg fdcA ||  