This program can be used to calculate various parameters related to X-linked recessive disorders. It is particularly useful for calculating the prior population female carrier risk (or carrier rate), which is the starting point for many genetic risk calculations for X-linked recessive disorders. To use this calculator it is necessary to first specify the male:female de novo mutation rate ratio (i.e. ν:μ; e.g. a 10:1 ratio would indicate that new mutations arise 10 times more often on the paternal allele than on the maternal allele). After specifying values for two of the following four additional parameters, values for the other two are calculated: prevalence in males (p), genetic fitness of affected males (f), female carrier rate (c), and de novo mutation rate (ν or μ). Tip: Enter values either as a decimal (e.g. 0.0001) or as a formula (e.g. =1/10000). Usage notes to follow soon.