Craft a composition that integrates the assigned alphabet-related musical pattern and the provided melodic theme.
X:1
L:1/8
M:4/4
K:G
['GA B2 BB Bc dB A2 AA', 'gf e2 dd d2']  
X:1
L:1/8
M:4/4
K:G
 GA | B2 BB Bc dB | A2 AA A2 Bc | d2 cB c2 BA | G2 GG G2 :: gf | e2 dd d2 GA | B2 BB B2 gf | 
 e2 dd d2 cA | AGFE D2 GA | B2 BB B2 gB | A2 AA A2 Bc | dgdB c2 BA | G2 GG G2 :|  