Journal of Genetic Counseling

, Volume 21, Issue 2, pp 173–174 | Cite as

46 Chromosomes and Me

  • Joann Bodurtha
Professional Issues

It is astounding to me that the discovery of humans having 46 chromosomes is younger than I am. How could we have uncovered this truth so recently? Perhaps I am older than I feel? I suspect each of us working in genetics has some paper or lecture which frames our recognition that looking for scientific truth is a never-ending pursuit. It wasn’t until I was a faculty member that I realized professors at their most definitive are likely to be proven over time to be somewhat wrong. I have also come to know that “getting the math right” continues to underlie a lot of what we do in medical genetics and genetic counseling. My chosen defining moment occurred when I sat in a small crowded National Institutes of Health (NIH) office in 1978, interviewing Dr. J-H Tjio, the man who first counted 46 chromosomes under the microscope (Harper 2006; Tjio and Levan 1956).

My mentors in medical school encouraged me to do “away” rotations in genetics and epidemiology, so I met some of the founding mothers...


Genetic counseling Professional development Medical history 


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Copyright information

© National Society of Genetic Counselors, Inc. 2011

Authors and Affiliations

  1. 1.McKusick - Nathans Institute of Genetic MedicineJohns Hopkins UniversityBaltimoreUSA

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