The Karyotype of a complete mole is:
**Core Concept**
A complete mole is a type of gestational trophoblastic disease (GTD) characterized by the presence of an abnormal karyotype in the placental tissue. The karyotype of a complete mole typically arises from the fertilization of an empty egg by a single sperm, resulting in a triploid genotype.
**Why the Correct Answer is Right**
The karyotype of a complete mole is usually 46,XX with diploid paternal genetic material, indicating that the mole is of paternal origin. This occurs when an empty egg is fertilized by a single sperm, resulting in a triploid genotype. The extra set of chromosomes in a complete mole typically comes from the father, making the karyotype 46,XX, with the extra set of chromosomes being paternal in origin.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because a complete mole typically has a triploid karyotype, not a diploid one.
**Option B:** This option is incorrect because a complete mole typically arises from the fertilization of an empty egg, not two sperm.
**Option C:** This option is incorrect because a complete mole typically has a paternal origin, not a maternal one.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the karyotype of a complete mole is typically 46,XX, and this should be considered when evaluating patients with suspected GTD.
**Correct Answer: C. 46,XX**