Craft a composition that integrates the assigned alphabet-related musical pattern and the provided melodic theme.
X:1
L:1/8
Q:3/8=100
M:6/8
K:G
['GBG AFD EGE DCB, CEC B,DB,']  
X:1
L:1/8
Q:3/8=100
M:6/8
K:G
 D | GBG AFD | EGE DCB, | CEC B,DB, | A,BG FED | GBG AFD | EGE DCB, | CEC B,DB, | A,GF G2 |:  