recessive
Yes, as it is explained by Mendel's Law of Independent Assortment;The alleles for the genetic disorder are inherited from both parents, through the combined recessive gene expression :Tt x Tt = TT: 25%; Tt: 50%; tt: 25%Autosomal recessive disorders: Show up only in the homozygous recessive person (aa) who inherits a recessive allele from both parents, who were carriers (Aa xAa). (25% chance of this happening)Tay-Sachs: Enzyme that breaks down brain lipids is non-functional in homozygous recessives (tt). Buildup of lipids causes death by age 2-3. People with Ashkenazi Jewish ancestry are often carriers fro this trait.Heterozygote advantage; For some disease alleles, being a heterozygote offers protection against another disease.Tay-Sachs: Tt carriers are thought to be more resistant to tuberculosis. Research still needs to be done on this.http://www.biology.iupui.edu/biocourses/N100/2k4ch10mendelexcept.html