Misc Disorders I

Question 1

Fragile X

Answer 1

FMR1 X-linked; penetrance in females is 50-60% 200+ CGG trinucleotide repeats (56-200 premutation) LD, ADHD, tall, big ears, ASD Females: LD, POF or POI

Question 2

Prader Willi Syndrome

Answer 2

Abnl Methylation on chr 15; maternal UPD; good example of paternal imprinting 1/200,000 births Hyperphagia, obesity, almond shaped eyes, hypotonoia, DD

Question 3

Angelman Syndrome

Answer 3

Abnl Methylation on chr 15; paternal UPD; ; good example of maternal imprinting 1/15,000 births severe DD, “happy” with laughter, like water, seizures, ataxia

Question 4

Kallmann syndrome

Answer 4

Anosomia, hypogonadism, infertility (males)

Question 5

Blepharophimosis syndrome

Answer 5

AD; FOXL2 With premature ovarian failure (BPES type I) or without (BPES type II) Alos: blepharophimosis, ptosis, epicanthus inversus, telecanthus, lop ears, ectropion, hypoplasia of superior orbital rims, and hypertelorism

Question 6

Treacher Collins syndrome

Answer 6

cleft lower lid, lacking zygomatic bones

Question 7

Miller Dietker syndrome

Answer 7

upslanting palpepral fissures

Question 8

Cornelia de Lange

Answer 8

Synophrys

Question 9

Waardenburg syndrome

Answer 9

Hearing loss, wide nasal bridge, white forelock

Question 10

Wolf-Hirschhorn syndrome

Answer 10

4p- Smooth philtrum

Question 11

Van der Woude syndrome

Answer 11

Lip pits, cleft palate

Question 12

Optiz Syndrome

Answer 12

hypertelorism, ankyglossia

Question 13

Pallister syndrome

Answer 13

Postaxial polydactyly

Question 14

Rubinstein-Taybi syndrome

Answer 14

Broad thumbs, behavioral issues

Question 15

Williams syndrome

Answer 15

chr 7 microdeletion cognitive impairments, microcphaly, elfinlike facial features, short stature, extreme friendliness, stellate iris

Question 16

CHARGE syndrome

Answer 16

CHD7 coloboma, choanal atresia, ear anomalies (triangular conchae, wide, cupped), retarded growth, dev delay, cardiac defects, genital abnormalities square face, broad nasal root, wide neck, sloping shoulders, facial asymmetry and palsy

Question 17

hereditary hemochromatosis

Answer 17

HFE; AR Overabsorption of iron leads to organ damage More common in males; good example of sex-limited inheritance

Question 18

Duchenne muscular dystrophy

Answer 18

X-linked good example of mosaicism in female carriers

Question 19

Hemophilia A

Answer 19

X-linked recessive

Question 20

hypophosphatemic rickets

Answer 20

X-linked dominant

Question 21

Rett syndrome

Answer 21

MECP2; X-linked dominant Lethal in hemizygous males

Question 22

hereditary paragangliomas

Answer 22

AD tumors in ganglia, pheochromocytoma example of imprinting - only affected if inherited from father

Question 23

retinitis pigmentosa

Answer 23

ORP1; AD, AR, or x-linked depending on mutation (allelic/locus heterogeneity)

Question 24

Retinoblastoma

Answer 24

AD; RB1 1 in 13,500-20,000 Leukoria, strabismus Two-hit hypothesis example because age of onset is infancy Subtypes: 13q deletion syndrome, low penetrant RB 40% of cases are hereditary; penetrance is high Clinical dx criteria: Bilateral or trilateral; OR Unilateral with fam hx