Develop a musical composition by integrating the alphabetically represented musical pattern and the supplied melodic theme.
X:1
L:1/8
M:6/8
K:G
['dBG GFG ABA ABd ef/g/e dBd', 'efg dBG', 'fg afaf', 'cd eA A2 eAgA fA A2 fAaA']  
X:1
L:1/8
M:6/8
K:G
 g | dBG GFG | ABA ABd | ef/g/e dBd | gGG Gge | dBG GFG | ABA ABd | ef/g/e dBd | gGG G2 |: e | 
 def gfg | efg a2 f | gab efg | dBG AGF | G>AG BGG | cGG dGG | ecd efg | dBG G2 :|[M:4/4][K:D] fg | 
 afaf dfed | cdea ABAG | FAdf gfed | ceAA A2 fg | afaf dfaf | edcB ABAG | FAdf Bgec | d2 d2 d2 :: 
 cd | eA A2 eAgA | fA A2 fAaA | gfed dcB^A | ^ABBB B2 =AG | FAd=c BGed | cAfe dBgf | eAag fedc | 
 d2 d2 d2 :|  