Karyotyping of products of conception from a patient with a partial hydatidiform mole is most likely to show which result?
- A 46,XX entirely paternal in origin
- B 69,XXY triploid with one maternal and two paternal haploid sets ✓
- C 45,X monosomy
- D 47,XY,+21 trisomy
Correct answer: B. 69,XXY triploid with one maternal and two paternal haploid sets
Explanation
Partial mole results from fertilisation of a normal ovum by two sperm (dispermy), giving a triploid conceptus, classically 69,XXY or 69,XXX. Complete mole is diploid, typically 46,XX, with all nuclear genetic material paternally derived and no fetus. Monosomy 45,X produces a blighted ovum, not molar change, and trisomy 21 is unrelated. This karyotypic distinction underlies the presence of fetal parts in partial but not complete moles.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.