Lecture 2 - Prenatal Development

Question 1

in early stages, there is ____ development. ie, portions of a region can be removed and there can be ____ development

Answer 1

regulative;

normal

Question 2

in later stages, there is _____ development. ie cells have become ____ and removal of a portion of an embryo will (allow or not allow) normal development

Answer 2

mosaic;
committed;
will not allow

Question 3

preimplantation cells are said to be ____ and can withstand some damage without effect

Answer 3

pluripotent

Question 4

narrowly, ____ is a structural abnormality or anomly which is present at birth

Answer 4

dysmorphology

Question 5

a ____ birth defect is a defect that requires medical/surgical intervention, is a major cause of cosmetic concern, or causes life-long disability or death. what is an example?

Answer 5

major;

cleft lip

Question 6

a ____ birth defect is one that does not require intervention, is not of major cosmetic conern, or does not cause life long disability or death. example is ____

Answer 6

minor;

cinodactyly of 5th finger

Question 7

which constitutes the majority of features of most dysmorphic syndromes, major or minor birth defects?

Answer 7

minor

Question 8

holoprosencephaly:
failure of _____;
may be related to mutations in ____;
seen in trisomy ___

Answer 8

left/right hemispheres to separate;
sonic hedge hog;
13

Question 9

holoprosencephaly:
___Telorism;
severe form can cause ____ or ____;
cleft lip

Answer 9

hypo;

cyclopia, proboscis

Question 10

sonic hedgehog:
inheritance?
requires ____ for activiation
do mutations have to occur in the gene or can they occur at a distance?

Answer 10

autosomal dominant, incomplete penetrance;
cholesterol;
can occur at a distance (“position effect”)

Question 11

a _____ is an intrinsic defect in the embryo that causes a structural defect due to an error in morphogenesis

Answer 11

malformation

Question 12

what is an example of a malformation?

Answer 12

cleft lip, neural tube defect (NTDs)

Question 13

NTD:

due to failure of ____ to fuse. occurs during ____ of development.

Answer 13

neuropores;

3rd/4th week

Question 14

NTD:

____ occurs when the rostral neuropore doesn’t fuse. when the caudal neuropore doesn’t close, ___ occurs

Answer 14

anencephaly;

spina bifida

Question 15

NTD:
associated with low _____ before conception/during pregnancy;
2 diagnostic findings in amniotic fluid?

Answer 15

folic acid;
increased AchE;
increased AFP (except for spina bifida occulta)

Question 16

deformation:

due to _____ disruption of fetus. during or after embryonic period?

Answer 16

extrinsic;

after

Question 17

deformations can be ____ (abnormal force outside uterus) or ____ (force within uterus)

Answer 17

extrinsic, intrinsic

Question 18

____ is persistent flexure or contracture of a joint.

Answer 18

arthrogryposis

Question 19

_____ = abnormal development of a specific fetal tissue ie achondroplasia

Answer 19

dysplasia

Question 20

_____ = secondary breakdown of previously normal tissue/structure. example = ______

Answer 20

disruption;

amniotic bands –> limb amputation

Question 21

_____ = abnormalities result from a single primary embryological event. 2 examples?

Answer 21

sequence;

pierre robin, potter

Question 22

pierre robin sequence:

hypoplasia of ____ causes ____ shaped ____ palate; posterior placed ____ and airway ____

Answer 22

mandible;
U-shaped cleft palate;
tongue, obstruction

Question 23

potter sequence:

usually due to ____ agenesis–> ___amnios –> ____ and ____ abnormalities. death from _____

Answer 23

renal; oligo;
facial, limb;
pulmonary hypoplasia

Question 24

____ = low frequency clustering of specific defects without clear genetic etiology

Answer 24

association

Question 25

CHARGE syndrome:
C = eye \_\_\_\_;
H = \_\_\_\_ anomalies
A = \_\_\_\_ atresia
R = \_\_\_\_\_
G = \_\_\_\_ anomalies
E = \_\_\_\_ anomalies

Answer 25

colobomas;
heart;
retardation (mental/somatic);
genital;
ear (sometimes deafness

Question 26

CHARGE = due to mutations in ____, which is a chromodomain/helicase/DNA binding protein

Answer 26

CHD7

autosomal dominant

Question 27

beckwith-wiedemann syndrome:

___ tumor, ___ glossia, ____ (musculoskeletal effect); ____ organs

Answer 27

wilms;
macro;
hemihypertrophy;
large (ie organomegaly)

also renal probs, normal intelligence

Question 28

beckwith:
due to imprinting of H19 and ____, which promotes growth;
9 fold higher risk with ….

Answer 28

IGF2;

In-vitro fertillization