What wonder if the Germanic genes have more presence than the Gauls.
No, Gaulish genes (well, at least Italo-Celtic haplogroup R1b-S116 and R1b-S28 + some G2a) are overwhelmingly dominant in northern Italy (50 to 70%), Lombardy included. The haplogroups that can be imputed to the Germanic invasions represent about 10% of the population.