Three dominant traits of corn seedlings, tunicate seed (T-), glossy appearance (G-), and liguled stem (L-), are studied along with their recessive counterparts, nontunicate (tt), nonglossy (gg), and liguleless (ll). A trihybrid plant with the three dominant traits is crossed to a nontunicate, nonglossy, liguleless plant. Kernels on ears of progeny plants are scored for the traits, with the following results:

Phenotype                                     Number
Tunicate, glossy, liguled                   102
Tunicate, glossy, liguleless               106
Tunicate, nonglossy, liguled               18
Tunicate, nonglossy, liguleless           20
Nontunicate, glossy, liguled                22
Nontunicate, glossy, liguleless            23
Nontunicate, nonglossy, liguled           99
Nontunicate, nonglossy, liguleless     110
                                                           500

Is there evidence of genetic linkage among any of these gene pairs? If so, identify the evidence.