RT Book, Section A1 Greenberg, Raymond S. A1 Daniels, Stephen R. A1 Flanders, W. Dana A1 Eley, John William A1 Boring, John R. SR Print(0) ID 546260 T1 Chapter 11. Epidemiologic Studies of Genetics T2 Medical Epidemiology, 4e YR 2005 FD 2005 PB The McGraw-Hill Companies PP New York, NY SN 9780071416375 LK accessmedicine.mhmedical.com/content.aspx?aid=546260 RD 2024/03/28 AB Familial aggregation of a disease is suggested when the recurrence risk among relatives of affected persons exceeds that among relatives of unaffected persons. In studies of twins, greater concordance for disease among monozygotic twins as compared with dizygotic twins suggests genetically determined susceptibility. If subjects with a high degree of inbreeding have an elevated risk of disease, an autosomal recessive pattern of inheritance may be suggested. Co-segregation refers to the tendency of alleles that are situated closely together on the chromosomes to be inherited together. Linkage of a marker gene (with a known location in the genome) and a disease susceptibility gene can suggest the particular chromosome involved and where on the chromosome the susceptibility gene is likely to be located. Segregation analysis of pedigrees is a complex statistical technique used to determine whether a disease has, at least in part, a genetic origin, and if so, the likely pattern of inheritance.