Sex-linkage

• Any gene carried on the X or Y chromosome is said to be sex linked

  There is no equivalent homologous portion on the Y chromosome
• Genetic diagrams showing sex-linked genes use different X chromosomes and a single Y chromosome to show the different genders
• Pedigree charts are used to trace the inheritance of characteristics which may or may not be sex-linked
• Approaching questions about pedigree charts

  • read key
  • annotate what you can work out
  • refer to specific individuals