A baby presenting with multiple deformities, cleft lip, cleft palate, microphaly, small eyes, scalp defect and polydactyly, seen in which syndrome
First, I remember that cleft lip and palate are seen in several syndromes. But the combination here is key. Microphaly (small head) and small eyes (microphthalmia) are significant. Scalp defects and polydactyly add more clues.
I think of some common syndromes with these features. Down syndrome has microphaly and other features, but not typically cleft lip/palate. Turner syndrome? No, that's different. Maybe a rare syndrome. Oh, there's something called Holoprosencephaly, but that's more about facial midline defects and brain issues.
Wait, what about Patau syndrome (Trisomy 13)? It's associated with cleft lip/palate, microphthalmia, polydactyly, and other malformations. Also, scalp defects like aplasia cutis can occur. The microphaly is a key point here. Trisomy 13 is a strong candidate.
Let me cross-check. Edwards syndrome (Trisomy 18) has other features like clenched hands and rocker bottom feet. So that's not it. Cri-du-chat has a high-pitched cry and microcephaly, but not the other features.
So the correct answer is likely Trisomy 13 (Patau syndrome). The key features here are the combination of clefts, microphthalmia, polydactyly, scalp defects, and microphaly. All fit Trisomy 13. The other options don't fit as well.
Now, the options given are A to D, but the correct answer is D. I need to make sure I explain why the other options are wrong. For example, if another option is Turner syndrome, that's incorrect because it doesn't have these features. Similarly, Down syndrome (Trisomy 21) has different characteristics. Edwards is Trisomy 18, which has different malformations. So the explanation should highlight that Trisomy 13 is the only one that matches all the listed features.
**Core Concept**
This question tests recognition of **Trisomy 13 (Patau syndrome)**, a chromosomal disorder characterized by severe congenital malformations, including craniofacial, ocular, and limb abnormalities. Key features include **cleft lip/palate**, **microphthalmia**, **polycystic kidneys**, and **polydactyly**.
**Why the Correct Answer is Right**
Trisomy 13 (Patau syndrome) is caused by **non-disjunction during meiosis**, leading to three copies of chromosome 13. The described features—**cleft lip/palate**, **microphaly**, **microphthalmia**, **scalp defects (aplasia cutis)**, and **polydactyly**—are classic manifestations. These result from disrupted embryonic development due to overexpression of genes on chromosome 13. **Polydactyly** arises from abnormal limb bud patterning, while **clefting** stems from