TABLE 3

Young Alu subfamilies copy number, inserts linked to disease, and polymorphism

Alu subfamilyEstimated copy numberInserted linked with diseaseaGeneral subfamily polymorphismb (%)
J, Sx, Sg1>1,000,0000
Y>200,0001±
Ya526407+26
Ya5a2401+++80c
Ya8700++50
Yb818523+20
Yb9800+36
Yc14003+25c
Yc2ND0+37.5c
  • ND, not determined.

  • a Previously published Alu elements linked with disease (Deininger and Batzer 1999).

  • b The proportion of polymorphic elements within each family is represented by the following: ±, rarely polymorphic elements are found; +, low percentage of polymorphic elements; ++, ~50% the elements are polymorphic; and +++, most of the elements are polymorphic.

  • c Percentage polymorphism was determined using a selected subgroup introducing a bias.