genetics and anomalies Flashcards
what is unique about homeobox genes?
one master gene regulates the expression of many genes
what type of things do homeobox genes control?
induction
differentiation
apoptosis
morphogenesis
patterning
what triggers homeobox genes?
growth factors
list the growth factors involved in signally to homeobox genes?
TGF
EGF
FGF
BMPs
what are the genes that control tooth bud development?
MSX1 and MSX2
what is the signally cascade known as?
morphogenetic cascade
what does autosomal dominant mean?
that only one faulty gene from one parent is needed to cause disease
what generations would an autosomal dominant condition be seen in?
all generations
what are the chances of having an affected child with AD?
50%
and diseases severity is variable
what are examples of AD diseases ?
-dwarfism
-couzens syndrome
-cleidocranial dysostosis
-dentogenesis imperfecta- opalescent dentine- translucent and discoloured
-Van Der Woude- cleft palate/lip and lip pits
what is meant by autosomal recessive inheritance?
both faulty genes from each parent is required to cause disease
does AR affect all generations ?
no, normally only 1
what is the chances your child will be affected by AR inheritance?
1 in 4
what makes the risk of AR disease higher?
consanguineous (same blood line)
what is x linked recessive?
where fault can only be on x chromosome
would someone with an x recessive show symptoms of disease?
they may show mild
what is the outcome of x recessive inheritance ?
1/2 females will be carriers
1/2 males will be affected
what are examples of x recessive inheritance?
ectodermal dysplasia
hypodontia and conical teeth
what is x inactivation inheritance?
when only one X chromosome is active in females
what is another word for x inactivation?
lyonisation
what are multifactorial disorders?
these are disorders that are caused by both genetic and environmental factors
what does multifactorial threshold mean?
this means traits only present if genetic and environmental factors are met? genetics makes them susceptible and environmental factors are triggers
what are examples of multifactorial disorders?
cp
cl
diabetes
heart disease
asthma
what are public health interventions?
total pop-diet nutrition
targeted- screening
what type of screening is used for these genetic disorders?
genetic screening
- to locate genetic changes or genetic abnormalities comparing to humans without the disease using markers (human genome project-location is known)
