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Flashcards in Chromosomal problems Deck (11):

Downs syndrome testing

first trimester: incr. nuchal translucency, hypoplastic nasal bone, serum PAPP-A down, incr. free beta HCG
second trimester: incr. beta HCG, incr. inhibit A. Decr. alpha-fetoprotein and decr. estriol


Important findings with Down's

early Alzheimers, singal palmar crease, Hirsprung disease (neural crest migration problem where the intestines aren't fully innervated), hear disease, exp. atrial septal defects, and incr. risk of AML, ALL, Bushfield spots
(so, head to toe: eyes, heart, blood, gut, brain)


Edwards syndrome symptoms

trisomy 18. small jaw, low set ears, clenched hands, prominent occiput, congenital heart disease


Edwards syndrome screening

first trimester: PAPP-A and free beta hCG down.
second trimester: decr. alpha fetoprotein, decr. beta HCG, decr. estriol, decr or normal inhibin A


Patau syndrome

trisomy 13. causes microopthalmia, microcephaly, cleft lip/palate, holoprosencephaly, polydactyly, and congenital heard disease


screens for Patau syndrome

first trimester: decr. beta hCG, decr. PAPP-A, incr. nuchal transparency


What chromosomes are most likely to have a Robersonian translocation

13, 14. 15, 21, 22



microdeletion of the short arm of chromosome 5. microcephaly, intellectual disability, high pitched mewing, epicanthal folds, VSD


Williams syndrome

microdeletion of chromosome 7. elfin facies, intellectual disability, hypercalcemia, verbal skills, extreme friendliness with strangers, and CV problems


22q11 deletion syndromes

CATCH-22: cleft palate, abnormal facies, thymic aplasia, cardiac defects, and hypocalcemia from parathyroid dysplasia. causes aberrant development of the 3rd and 4th branchial pouches


Velocardiofacial syndrome

palate, facial and cardiac defects d/t 22q11 deletion syndrome