MEXICO CITY, Jan 27 (Reuters) - The Mexican banking association said on Wednesday that there was no institutional collusion by banking institutions, only by some individuals, two days after Mexico’s antitrust watchdog Cofece slapped fines on seven international banks and traders. Cofece fined the banks and traders a total of 35 million pesos ($1.75 million) for market manipulation and collusion in the government bond market about a decade ago. (Reporting by Abraham Gonzalez, writing by Laura Gottesdiener; Editing by Frank Jack Daniel)