So what do we mean by autosomal recessive? So let's suppose the gene we're talking about is color blindness. And let's designate color blindness with the gene given by letter B. So the dominant gene is given by uppercase B, and the recessive gene is given by lowercase B. So let's take a look at our pedigree. Or actually, let's just kind of denote these as this is our dominant gene and this is our recessive gene that basically codes four color blindness.