A Family 6 cellulase variant enzyme comprising one or more than one amino acid substitution selected from a basic, polar or non-polar amino acid at position 103, a valine or isoleucine at position 136, a tyrosine at position 186, a glutamic acid or glutamine at position 365 and a glutamine at position 410 is provided (said position determined form alignment of the parental Family 6 with SEQ ID NO: 1). Genetic constructs and genetically modified microbes comprising DNA sequences encoding the Family 6 cellulase variant are also provided. Family 6 cellulases of the invention display reduced inhibition by glucose relative to the parent Family 6 cellulases. Such cellulases find use in a variety of applications in industry, e.g., in the hydrolysis of pretreated lignocellulosic feedstock, that require cellulose activity in the presence glucose concentrations that would otherwise inhibit the activity of the parental enzyme.