Genetics Flashcards
different versions (a variant of the similar DNA sequence) of a gene that occupy the same locus
alleles
individuals with identical alleles for a given locus
homozygous
individual with different alleles for a particular locus
heterozygous
the physical manifestation of the gene,
depends on a person’s gene, gene-gene, and gene-environment interactions
phenotype
set of genes of an organism
genotype
unit of inheritance
gene
carrier of genes
chromosome
specific location of a gene (DNA sequence) on a chromosome
locus
a gene in a pair specifies the phenotype instead of the other gene
dominant trait
traits or disease manifest only when both copies of the gene are the same
recessive trait
dictated by the alleles
trait
Normal karyotype for females
46,XX
Normal karyotype for males
46,XY
mga under ng
Autosomal Dominant Inheritance
Familial Hypercholesterolemia
Marfan Syndrome
Ehlers-Danlos Syndrome
Neurofibromatosis Type 1
(Von Recklinghausen Disease)
mga under ng
Autosomal Recessive Trait
Classic Phenylketonuria
Maple Syrup Urine (MSU) Disease
Galactosemia
Congenital Adrenal Hyperplasia
mga under ng
X-LINKED DOMINANT INHERITANCE
Focal Dermal Hypoplasia (Goltz syndrome)
Rett syndrome
mga under ng
X-LINKED RECESSIVE INHERITANCE
G6PD Deficiency
Hemophilia
Duchenne Muscular Dystrophy (DMD)
Connective tissue disease 1:5000
Mutation in fibrillin-1 (FBN1) gene on chromosome 15 q
(tall stature, unusually long slender limbs, scoliosis, chest wall deformities, arachnodactyly, hyperextensibility of the joints)
Marfan syndrome
INCREASED levels of cholesterol
Management: Statins (HMG CoA reductase inhibitor)
Familial Hypercholesterolemia
Marfan syndrome gene mutation
Mutation in fibrillin-1 (FBN1) gene on chromosome 15 q
Defect in collagen structure or synthesis ➔ abnormal production and secretion of collagen
Ehlers-Danlos Syndrome
Neurofibromatosis Type 1 (Von Recklinghausen Disease)
defect in
tumor suppressor gene NF-1 on chromosome 17
multiple neurofibromas, café-au-lait spots, Lisch nodules (benign growth in the iris), optic pathway gliomas, learning disabilities, short stature, seizures, hypertension, malignancies
Neurofibromatosis Type 1 (Von Recklinghausen Disease)
must use soya formula
Galactosemia
6 diseses covered by screening tests
G6PD Congenital hypothyroidism Classic Phenylketonuria Maple Syrup Urine (MSU) Disease Galactosemia Congenital Adrenal Hyperplasia
last 4 is Autosomal Recessive Trait
Deficiency of liver enzyme phenylalanine hydroxylase
Classic Phenylketonuria
diet for Classic Phenylketonuria and Maple Syrup Urine (MSU) Disease
low protein
Accumulation of branched chain amino acids leucine, isoleucine and valine
Maple Syrup Urine (MSU) Disease
Deficiency of any of the enzymes required for the synthesis of aldosterone and cortisol: 21hydroxylase, 11βhydroxylase, 3βhydroxysteroid and 17αhydroxylase, congenital lipoid hyperplasia, P450 oxidoreductase deficiency
Congenital Adrenal Hyperplasia
avoidance of fava beans
G6PD
Trisomy 21
Down’s syndrome
Trisomy 13
Patau Syndrome
Trisomy 18
Edward Syndrome
XXY
Klinefelter Syndrome
genetic testing for DNA
Southern blot
genetic testing for RNA
Northern blot
genetic testing for dystrophy
Western blot
rate-limiting enzyme in hexose monophosphate shunt
G6PD
Tympanitic abdomen
Colic
lack of clotting factor VIII
Hemophilia A
lack of clotting factor IX
Hemophilia B
Hallmark: hemarthrosis (ankles); prolonged bleeding episodes, easy bruisability, IM hematoma
Hemophilia
“runs in the family”
multifactorial
most common inborn error of metabolism
MSU
a condition with the deficiency of an enzyme that is required in the synthesis of cortisol and aldosterone: females would manifest with ambiguous genitalia, salt-wasting type adrenal crisis
CAH
puppet-like gait
Angelman syndrome
type of stem cell that differentiate into embryonic and extraembryonic
totipotent
bone marrow stem cell is example of
hematopoietic
most common chromosomal autosomal abnormality
Trisomy 21/ Down’s syndrome
examination of abdomen
inspection - palpation - percussion - auscultation
