Week 2 chromosomal disorders

Question 1

What is the genetic abnormality associated with Down syndrome?

Answer 1

Trisomy 21; sometimes 46,X_(t21;21) or 46,X(t21;14)

Question 2

What are the signs and symptoms associated with Down syndrome?

Answer 2

Facial dysmorphology, bent 5th fingers, single palmar crease, 40-50% cardiac defects, hearing loss, strabismus, moderate intellectual disability

Question 3

What are the clinical manifestations of Patau syndrome?

Answer 3

***Polydactly

Question 4

What are the clinical manifestations of Patau syndrome?

Answer 4

Polydactly, atypical median cleft lip/palate, facial dysmorphology, flexed fingers, microcephaly

Question 5

What is the genetic abnormality associated with Klinefelter syndrome?

Answer 5

47,XXY

Question 6

What are the clinical manifestations of Edward syndrome?

Answer 6

Facial dysmorphology, short sternum, clenched fists with overlapping fingers, genital anomalies, syndactly, cardiac/renal defects, severe intellectual disability

Question 7

What are the clinical manifestations of 22q11.2 deletion syndrome?

Answer 7

Hypocalcemia, interrupted aortic arch, thymus/parathyroid abnormalities, mild facial dysmorphology (formerly considered DiGeorge syndrome); ventricular septal defect, palatal abnormalities, growth deficiency, intellectual disability (formerly considered velocardiofacial syndrome)

Question 8

What is the inheritance pattern of 22q11.2 deletion syndrome?

Answer 8

Autosomal dominant

Question 9

What is the genetic abnormality associated with Williams syndrome?

Answer 9

Various deletions along chromosome 7

Question 10

What are the clinical manifestations of Williams syndrome?

Answer 10

Blonde hair/blue eyes, facial dysmorphology, “cocktail personality,” developmental delay, supravalvular aortic stenosis, hypercalcemia

Question 11

What is the genetic abnormality associated with WAGR?

Answer 11

Deletion of PAX6 and WT1 genes at 11p13

Question 12

What are the clinical manifestations associated with WAGR?

Answer 12

Wilms tumor of the kidney, aniridia (leads to blindness), genital anomalies, intellectual disability (R)

Question 13

What are the clinical manifestations associated with Klinefelter syndrome?

Answer 13

Tall, long limbs, hypogonadism, azospermia, increased risk of breast cancer, around 10 point IQ deficit compared to family history

Question 14

What is the inheritance pattern of Williams syndrome?

Answer 14

Autosomal dominant

Question 15

What is the genetic abnormality associated with Turner syndrome?

Answer 15

45,X; sometimes mosaic for Y chromosome

Question 16

What are the clinical manifestations associated with Turner syndrome?

Answer 16

Edema of hands and feet, webbed neck, lack of puberty, short stature, coarctation of aorta