Question

Chromosome number of partial hydatidiform mole is

• A. 46 XX
• B. 45 XO
• C. 46 XXY
• D. 69 XXX

Answer 1

The Correct Option is D

Step 1: A partial mole arises from an excess paternal chromosome set, classically when two sperms fertilise a single egg, so the conceptus carries three haploid sets.
Step 2: Three haploid sets of 23 chromosomes give a total of 69, with sex-chromosome combinations of XXX, XXY or XYY. This triploidy is the genetic signature of a partial mole and explains the mix of placental molar tissue with some fetal parts.
Step 3: A complete mole, in contrast, is diploid (46,XX or 46,XY) and entirely paternal. The non-molar options 45,XO and 46,XXY are unrelated aneuploidy syndromes. Therefore the partial mole karyotype is 69,XXX.
\[\boxed{\text{69 XXX}}\]