1956 AD
Human chromosome count established as 46
Genética y biotecnología · Citogenética · Cromosomas humanos
Tjio and Levan published a count of 46 chromosomes in human cells, correcting a number accepted for decades. The improvement depended on cell-preparation techniques and showed how instruments shape what cytogenetics can see.
Precision, calendar, and review
- Start
- year · no uncertainty qualifier in this record
- Calendar and convention
- Historical-era years; the source calendar is not identified. No conversion of days is assumed.
- Year zero
- The scale goes from 1 BCE to 1 CE without year zero. Changing era names changes labels only.
- Documentary review
- Date not recorded
Reading the date: point event.
Sources
- pubmed.ncbi.nlm.nih.gov (opens in a new tab)
Source provenance and scope
- Publication date
- Pending verification: the source could not be accessed
- Bibliographic date checked
- 2026-09-23
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