data analysis for partial two-by-two factorial design

Question

[ycding]

I need to analyze data generated from a partial two-by-two factorial design: two levels for drug A (yes, no), two levels for drug B (yes, no); however, data points are available only for three groups, no drugA/no drugB, yes drugA/no drugB, yes drugA/yes drug B, omitting the fourth group of no drugA/yes drugB. I think we can not investigate interaction between drug A and drug B, can I still run model using R as usual: response variable = drug A + drug B? any suggestion is appreciated.

Thank you very much!

Yuan Chun Ding

[Kevin Blighe]

You're analysing genetic data?