KaryoDraw

Marker chromosome

47,XX,+mar

Also known as: +mar, supernumerary marker, ESAC

47,XX,+mar shows a supernumerary marker chromosome, a small extra chromosome whose origin cannot be identified by banding alone. Further testing such as microarray or FISH is used to characterize it.

Open in the interactive visualizer →

mar
mar
Marker chromosome (47,XX,+mar) drawn by KaryoDraw, showing the involved chromosomes with their normal homolog.

What the notation means

47
total chromosome count (normal is 46)
XX
sex chromosomes: two X (usual female karyotype)
+mar
a MARKER chromosome (mar): a small extra chromosome whose origin can't be identified by banding alone

KaryoDraw is a free ISCN 2024 karyotype visualizer, a StudyRare tool. It is an educational visualizer of cytogenetic nomenclature, not a diagnostic tool.