If you have any non-numeric character in the character variable the output will be missing and your log will contain a. NOTE: Invalid Data message everytime you have a non-numeric character in your data. So you could get 10, 20, 50 or more notes in your log.
1. A man with hemophilia (a recessive, sex-linked blood clotting disorder) has a daughter of normal phenotype. She marries a man who is normal for the trait. XH-normal. Xh-hemophilia. Since this is a recessive disorder, one XH allele will give a normal phenotype. When the offspring do not have a XH and only have the Xh allele/alleles they will have the hemophilia condition. Man's genotype is XhY. Daughter's genotype is XHXh (She got the Xh from her father.
Sex-linked Traits. If a gene is found only on the X chromosome and not the Y chromosome, it is said to be a sex-linked trait. Because the gene controlling the trait is located on the sex chromosome, sex linkage is linked to the gender of the individual. Usually such genes are found on the X chromosome. The Y chromosome is thus missing such genes (See Diagram above.). The result is that females will have two copies of the sex-linked gene while males will only have one copy of this gene.