Lecture 2 - Prenatal Development Flashcards
in early stages, there is ____ development. ie, portions of a region can be removed and there can be ____ development
regulative;
normal
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
mosaic;
committed;
will not allow
preimplantation cells are said to be ____ and can withstand some damage without effect
pluripotent
narrowly, ____ is a structural abnormality or anomly which is present at birth
dysmorphology
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?
major;
cleft lip
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 ____
minor;
cinodactyly of 5th finger
which constitutes the majority of features of most dysmorphic syndromes, major or minor birth defects?
minor
holoprosencephaly:
failure of _____;
may be related to mutations in ____;
seen in trisomy ___
left/right hemispheres to separate;
sonic hedge hog;
13
holoprosencephaly:
___Telorism;
severe form can cause ____ or ____;
cleft lip
hypo;
cyclopia, proboscis
sonic hedgehog:
inheritance?
requires ____ for activiation
do mutations have to occur in the gene or can they occur at a distance?
autosomal dominant, incomplete penetrance;
cholesterol;
can occur at a distance (“position effect”)
a _____ is an intrinsic defect in the embryo that causes a structural defect due to an error in morphogenesis
malformation
what is an example of a malformation?
cleft lip, neural tube defect (NTDs)
NTD:
due to failure of ____ to fuse. occurs during ____ of development.
neuropores;
3rd/4th week
NTD:
____ occurs when the rostral neuropore doesn’t fuse. when the caudal neuropore doesn’t close, ___ occurs
anencephaly;
spina bifida
NTD:
associated with low _____ before conception/during pregnancy;
2 diagnostic findings in amniotic fluid?
folic acid;
increased AchE;
increased AFP (except for spina bifida occulta)
deformation:
due to _____ disruption of fetus. during or after embryonic period?
extrinsic;
after
deformations can be ____ (abnormal force outside uterus) or ____ (force within uterus)
extrinsic, intrinsic
____ is persistent flexure or contracture of a joint.
arthrogryposis
_____ = abnormal development of a specific fetal tissue ie achondroplasia
dysplasia
_____ = secondary breakdown of previously normal tissue/structure. example = ______
disruption;
amniotic bands –> limb amputation
_____ = abnormalities result from a single primary embryological event. 2 examples?
sequence;
pierre robin, potter
pierre robin sequence:
hypoplasia of ____ causes ____ shaped ____ palate; posterior placed ____ and airway ____
mandible;
U-shaped cleft palate;
tongue, obstruction
potter sequence:
usually due to ____ agenesis–> ___amnios –> ____ and ____ abnormalities. death from _____
renal; oligo;
facial, limb;
pulmonary hypoplasia
____ = low frequency clustering of specific defects without clear genetic etiology
association
CHARGE syndrome: C = eye \_\_\_\_; H = \_\_\_\_ anomalies A = \_\_\_\_ atresia R = \_\_\_\_\_ G = \_\_\_\_ anomalies E = \_\_\_\_ anomalies
colobomas; heart; retardation (mental/somatic); genital; ear (sometimes deafness
CHARGE = due to mutations in ____, which is a chromodomain/helicase/DNA binding protein
CHD7
autosomal dominant
beckwith-wiedemann syndrome:
___ tumor, ___ glossia, ____ (musculoskeletal effect); ____ organs
wilms;
macro;
hemihypertrophy;
large (ie organomegaly)
also renal probs, normal intelligence
beckwith:
due to imprinting of H19 and ____, which promotes growth;
9 fold higher risk with ….
IGF2;
In-vitro fertillization
