Yes. The genotype of Blood group A+ can be either Ia+Ia+ or Ia+Ia- whereas genotype of Blood group A- will be Ia-Ia-.
If both parents are with Ia+Ia+ genoytpes, then the child will also be Ia+ia+ (A +) always. But if one parent is Ia+Ia+ and the other is Ia+Ia-, the child will be either Ia+Ia+ (A+) or Ia+Ia- (A+).
If both parents are Ia+Ia-, the child will be Ia+ia+ (A+), Ia+Ia- (A+) or Ia-Ia- (A negative)
