1. Buckton KE, Spowart G, Newton MS, Evans HJ : Forty four probands with an additional ‘marker’ chromosome. Hum Genet 1985; 69: 353–370.
2. Warburton D : De novo balanced chromosome rearrangements and extra marker chromosomes identified at prenatal diagnosis: clinical significance and distribution of breakpoints. Am J Hum Genet 1991; 49: 995–1013.
3. Hook EB, Cross PK : Extra structurally abnormal chromosomes (ESAC) detected at amniocentesis: frequency in approximately 75 000 prenatal cytogenetic diagnoses and associations with maternal and paternal age. Am J Hum Genet 1987; 40: 83–101.
4. Blennow E, Bui TH, Kristoffersson U et al: Swedish survey on extra structurally abnormal chromosomes in 39 105 consecutive prenatal diagnoses: prevalence and characterization by fluorescence in situ hybridization. Prenat Diagn 1994; 14: 1019–1028.
5. Blennow E, Anneren G, Bui TH, Berggren E, Asadi E, Nordenskjold M : Characterization of supernumerary ring marker chromosomes by fluorescence in situ hybridization (FISH). Am J Hum Genet 1993; 53: 433–442.