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:G
['(G>A) (B<d)(b>a) (g<e)(e>g) (d<B)(B>d)', '(B<d)(d>e) d>BA>G']  
X:1
L:1/8
M:4/4
K:G
{DEF} G2 (G>A) (B<d)(b>a) | (g<e)(e>g) (d<B)(B>d) | (e>c)(A>c) (d>B)(G>B) | 
 (A>G)(F>E) (D>C)(B,>A,) | G,2 (G>A) (B<d)(b>a) | (g<e)(e>g) (d<B)(B>d) | (e>c)(A<c) (d>B)(G>B) | 
 A>DE>F G2 G2 :: (B<d)(d>e) d>BA>G | (c>e)e>d e>fg>e | (B<d)(d>e) (d>B)(G>B) | 
 (A>G)(F>E) D>CB,>A, | (B<d)(d>e) d>BA>G | (c>e)(e>d) e>fg>e | (B<d)d>e d>BG>B | B>AG>F G2 G2 :|  