Complete hydatidiform mole (CHM) is genetically characterized as:
- A 69,XXX or 69,XXY — triploid with one maternal and two paternal haploid sets
- B 46,XX — one maternal and one paternal set (biparental)
- C 46,XY or 46,XX — entirely paternally derived (androgenesis) with no maternal nuclear contribution ✓
- D 47,XXY — two maternal and one paternal set
Correct answer: C. 46,XY or 46,XX — entirely paternally derived (androgenesis) with no maternal nuclear contribution
Explanation
Complete hydatidiform mole has a diploid genome that is entirely of paternal origin (androgenesis). Most (90%) are 46,XX from duplication of a single sperm (dispermy also produces 46,XY). There is no functional maternal nuclear DNA. The maternal mitochondrial DNA is present but the nuclear genome is purely paternal. Partial moles are triploid (69,XXX or 69,XXY) with one maternal and two paternal haploid sets. This distinction has clinical importance as CHM has higher malignant transformation potential than partial mole.
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.