OKTs Flashcards
1
Q
what pattern is AD inheritance?
A
vertical inheritance
2
Q
what is Marfan Syndrome?
A
it is an AD condition that presents with dislocation of the lens of the eye
3
Q
what is a carrier?
A
it is an individuals that it heterozygous for a recessive condition
4
Q
what is the phenotypes?
A
how the genetic change manifest themselves
5
Q
what shape is mitochondrial DNA?
A
circular
6
Q
what is a psuedogene?
A
it is an evolutionary remnant in the form of a DNA sequence. It resembles a gene elsewhere in the genome closely but has mutations that appear to render it inactive
7
Q
what is anticipation?
A
it is increasing severity of inherited disease as it passes down through successive generations
8
Q
what is the karyotype?
A
we have 46 chromosomes in ours and it was correctly defined in 1956
9
Q
what is consanguinity?
A
it is a aspect of family structure that increases the risk of autosomal recessive inheritance
10
Q
where does mitchondrial inheritance come from?
A
maternal
11
Q
what is the nucleosome?
A
it is the first level of assemble of the genome into chromatin for gene regulation through chemical modifications - they are units of chromatin containing around 200bp of DNA wound around a histone
12
Q
what is the role of the centromere?
A
to separate the p and q or short and long arms of the chromosome
13
Q
where are okazaki fragments found?
A
in DNA replication on the lagging strand
14
Q
what is the exon?
A
it is the part of the gene whos sequence is represented in mature mRNA
15
Q
what is a carcinoma?
A
it is a malignant epithelial tumour
16
Q
what is the most common type of autopsy?
A
the coroners autopsy
17
Q
what is histopathology?
A
it is the investigation and diagnosis of disease from the examination of tissues
18
Q
what is degranulation?
A
it is the release of preformed mediators from mast cells
19
Q
what is cytopenia?
A
a reduction in the number of blood cells
20
Q
what is a dendrocyte?
A
it is a type of APC
21
Q
what is the prognosis?
A
it is the anticipated course of a disease in terms of its cure, remission or fate
22
Q
what does the suffix penia denote?
A
lack of
23
Q
what is pathogenesis?
A
it is the mechanisms through which the aetiology of a disease produces its clinicopathological effects
24
Q
what is one of the mechanisms of tissue damage in type III hypersensitivity?
A
generation of active components of complement factors
25
how common is selective IgA deficiency?
it is the commonest primary defect of specific immunity in the UK
26
what is an important characteristic of a type IV hypersensitivity reaction?
delayed
27
what is the suffix that denotes an increased number of cells?
cytosis
28
what is aetiology?
it is the study of causes of a disease
29
what is integral to cell mediated immunity?
cytotoxic surface CD8+ T cells that respond to MHC FIB
30
what is bronchiecstasis?
it is the widening of the bronchi or of their branches
31
what is anaplasia?
it is usually in tumours and is the lack of normal differentiated state
32
what does dys in dysplasia mean?
disordered
33
what is special about IgG?
it is the only immunoglobulin that is able to cross the placenta
34
what is granuloma?
it is infectious or foreign material that cannot be degraded or removed and is therefore engulfed in inflammatory tissue
35
what does the T in T cell stand for?
thymus
36
what does thymic aplasia result in?
lack of T cells resulting in DiGeorge syndrome
37
what is SCID?
it is the acronym that is used for severe combined immunodeficiency that is seen in infants where the is a failure of both B and T lymphocyte function
38
what does meta as a prefix mean?
change from one state to another
39
what is a polymorphism?
it is a common genetic variant that is present in 1% or more of the population
40
what is glutamine for by?
the CAG trinucleotide that is involved in some neurodegenerative disorders - anticipation is part of this and is usually polymorphic
41
what does alternative splicing result in?
increased diversity of gene products
42
what mutations results in short limbed dwarfism?
a unique activating mutation at position 308 of the fibroblast growth factor receptor 3 - results in a wellknown form of achronoplasia
43
what is the structure of chromosomes after S phase of cell cycle?
each chromosome comprises two identical sister chromatids
44
what does Sanger sequencing depend on?
the synthesis of DNA strands in the presence of chain terminators
45
what does a missense mutation result in?
amino acid substitution
46
what are examples of sex chromosome aneuploidy?
Klinefelters - 47,XXY
| Turners - 45,X
47
what does a 45,XX-18 have?
monosomy
48
what is a robertsonian translocation?
it is when the two acrocentric chromosomes are fused - the vestigial short arms of acrocentric chromosomes differ in content from that of other chromosome arms as they contain no indispensable single copy genes
49
what is inversion?
it is an example of a recurrent mutation that is mediated by recombination between repeat sequences near the tip of the X chromosome and is commonly underlying haemophilia A
50
what is the result of a genetic bottleneck?
reduced diversity
51
what is alphoid?
a centromeric DNA repeat family
52
what is FISH?
it is a cytogenetic technique using DNA probes that examines a single locus
53
where is the splice acceptor site found?
it is found at the 5' boundary of all but the first exon in a gene - splice donor and splice sites in the primary RNA transcript are recognised by the splicing machinery - spliceosome
54
what are dizygotic twins?
non identical
55
what is a somatic mutation?
it is a non inheritable mutation because cells that have somatic mutations make non identical daughter cells. Provided this mutation occurs early enough in development the mutated cell can make up a large amount of the individual which may cause cancer or mosaicism
56
what is an association study?
it is a type of genome wide genetic study that is based on a population rather than familial inheritance and is a common approach to identifying the genetic contribution to common disease
57
what are terminator types of codon in bacteria?
TAG, TGA and TAA
58
what is LD?
linkage disequilibrium means that alleles on two adjacent genetic loci are not randomly assorted into haplotypes - if they are far apart on chromosome then they will be inherited independently but if they are close then will be coinherited
59
what is a reciprocal translocation?
two different chromosomes break and exchange material - if there is no loss it is known as balances
60
what is heritability?
it is the proportion of multifactorial causation of a common disease that can be attributed to genetic factors
61
what is an oncogene?
a gene whos expression tends to cause or promote cancer development
62
what does the prefix g mean in mutation descriptions?
genome
63
what does Williams syndrome result from?
a microdeletion in the elastin ELN gene
64
what base presents in RNA but not DNA?
uracil
65
what is a conservative mutation?
it is a substitution of a chemically similar amino acid
66
when is concordance greater?
when there is a genetic influence then concordance will be greater in identical than non identical twins
67
what is the chiasm?
it is the site of meitotic recombination that is an essential part of gametogenesis. It is also a source of errors that can result in chromosomal duplications and deletions
68
what is retinoblastoma?
it is an often hereditary cancer that is predominant in childhood and involves the eye
69
what happens with the BRCA1 mutation?
women with this mutation have a high chance of developing breast and ovarian cancer
70
what does polygenic mean
more than one gene contributes to the susceptibility of a disease
71
what is diptheria caused by?
a bacterial endotoxin
72
what is commensalism?
it is a symbiotic relationship where one organisms benefits and the other is neither benefiting or harmed
73
what is the main risk factors for atherosclerosis?
smoking
74
what is lockjaw?
it is an alternative name for tetanus
75
what is the final destination for an amniotic emboli?
the lungs
76
what is necrosis?
it is the process of cell death associated with ischaemia
77
what type of embolism is associated with many TIAs in the brain?
platelet
78
what can anaesthetic accidents result in?
neurogenic disruptive shock
79
what is recanalisation?
it is the process through which new blood vessels form within a thrombus meaning that blood can return to the occluded vessel
80
what maintains the low pH of the vagina?
bacterial species such as lactobacillus
81
what are cocci?
they are spherical bacteria
82
what is portal hypertension associated with?
cirrhosis
83
what is S. Saprohyticus?
it forms part of the normal flora of the vaginal orifice
84
what is gangrene?
it is a condition resulting from the infection of ischaemic tissue from anaerobic bacteria
85
what is mitral stenosis?
it is the pathological cause of raised left atrial pressure in pulmonary hypertension
86
what are endotoxins?
they are the disease causing lipopolysaccharide components of the outer membrane of bacteria
87
what species of bacteria is responsible for botulism?
belong to the clostridium species
88
how can haemorrhagic stroke result?
from ruptures aneurysm
89
what is tinea capitis?
it is ringworm affecting the scalp
90
what is an important growth factor released by platelets?
PDGF
91
what is the common fate of gangrenous toes associated with diabetes?
dry gangrene
92
what are pyogenic bacteria?
they are organisms that are involved in the formation of abscesses
93
what are microdeletions?
they are loss of chromosomal segments that are too small to be picked up on metaphase chromosome banding - they are detectable by FISH or aCGH such as in DiGeorge or WIlliams syndromes.
94
what does haploinsufficient mean?
when a gene will not tolerate the loss of one copy
95
what is methylation?
it is a DNA modification where the major site is the cytosine residue within a CG dinucleotide
96
how does a processed gene arise?
through retrotransposition - it is the reverse transcribed copy of mRNA and lacks introns
97
what is an obligate carrier?
in CL recessive it is a woman who must be a carrier due to her position on the pedigree. It could be a woman with two affected sons or one who is a daughter of an affected father
98
what is monozygotic?
it is identical twins - the genetic differences between DZ and MZ can show the heritability of a genetic trait
99
what is decipher?
it is a database of human chromosomal variation and its clinical effects, where a patients genome imbalance can be compared to those of a large number of deposited cases
100
what is microsatellite instability?
it is hallmark of impaired DNA mismatch repair which is used to allow replication errors to be recognised and put right - if it is impaired then errors can accumulate and cause cancer - deficient must be recognised through changes in size of STRs
101
what is the initiator codon?
it is the first triplet in the open reading frame of mRNA and is usually AUG which encodes methionine
102
what is the Knudsen effect?
it describes the inactivation of the TSG following a two step two hit mechanism and is used to describe the inheritance of retinoblastoma
103
when does a single nucleotide deletion cause a frameshift effect?
in protein coding region as it will truncate or scramble the protein and therefore render it non functional. If it is earlier on then it is much less likely to be tolerated however if it occurs close to the end of an open reading frame then might still produce a functional protein
104
what is 69XXY karyotype?
it is a triploidy syndrome with an extra set of 23 chromosomes that can be either paternally (diandric) or maternally (digynic) inherited. Digynic very occassionally are live born
105
`what is the telomere in mammals?
they are specialised structures that form the ends of the chromosome and are synthesised by an enzyme complex telomerase. In humans they are long stretched of repeat sequences of TTAGGG
106
what is cachexia?
it is an extreme form of systemic atrophy that may be associated with pathological loss of appetite
107
what is malignant?
it is a tumour that has begun to invade and metastasise
108
what is pleiomorphism?
it is when there is variation in size, shape and staining of malignant cells and their nuclei
109
what is Barretts Oesophagus?
it is the condition associated with metaplasia of the oesophagus due to chronic reflux
110
what is the bone relative to breast and primary lung cancer?
it is the favoured site of haematogenous spread
111
what is dysplasia?
it is the premalignant change in proliferation and differentiation that is associated with metaplasia
112
what is transcoelomic spread?
it is the spread of tumour cells across a body cavity such as around the peritoneal cavity
113
what does anaplastic mean?
it is the word used to describe a population of tumour cells that have become so differentiated that they cell type of origin is impossible to establish
114
what is metaplasia?
it is the reversible change of one cell type/differentiated state to another
115
what is the most common type of metastatic spread of tumour cells?
lymphatic
116
what is standard for blood gas analysis?
arterial samples
117
what are clonal tumour cells?
population that is derived from a single precursor cell
118
what can cigarette smoke lead to?
the transformation of pseudostratified ciliated bronchial epithelium to squamous epithelium
119
what happens to the thymus during normal ageing and why?
size decreases due to atrophy
120
what is acidosis?
when the blood pH is less than 7.4
121
what happens to the oxyhaemoglobin curve when pH decreases?
lower affinity so released more easily so shifts to right
122
what is an epigenetic change?
it is a modification to the genome that does not result in a change to the nucleotide sequence
123
what is uniparental disomy?
it is when both copies of the chromosome are are from one parents - may be completely without clinical effect or result in significant phenotypes such as Prader-Willi syndrome
124
what is warfarin?
it is an anticoagulant that shows genetically determined dosage sensitivity
125
what is Beckwith syndrome?
it is an overgrowth syndrome due to the dysregulation of the IGF2 gene - this is an insulin like growth factor that is important in foetal growth regulation and is encoded by an imprinted gene on 11p15
126
what regulates gene expression?
modifications to the histone class of protein
127
what does a deficiency in butyrylcholiesterase or pseudocholinesterase result in?
failure to wake up from an anaesthetic
128
what isw a CpG island?
it is a cluster of CG nucleotides frequently found near the 5' end of the gene - increased density where it is normally depleted - usually unmethylated but sometimes can become methylated and change gene transcriptional activity
129
what does Lynch syndrome result from?
hereditary non polyposis colon cancer - AD disorder due to a defect in any of the several genes involved in post replicative DNA repair
130
what is the hallmark of lynch syndrome?
microsatellite instability
131
what is the genetic abnormality behind complete hydatidiform moles ?
androgenesis
132
what does thiopurine methyltransferase show?
genetic variation in activity that results in toxicity in response to treatment with cytotoxic drugs which result in side effects due to bone marrow supression
133
what is lyonisation?
the term for X inactivation in females
134
when are preimplantation genetic tests done?
on in vitro cultured embryos
135
what are pseudoautosomal regions?
they are small shared regions shared between the X and Y chromosomes - exchange of material occurs in these regions during genetic recombination
136
what is name for the involuntary movement that is typical in HDD?
chorea
137
what are imprinted genes?
genes that are monoallelically expresses according to their parent of origin that may change according to stage of development
138
what is penetrance?
it is the frequency with which an inherited disorder manifests itself within gene carriers and is usually applied to dominant disorders that have incomplete penetrance
139
what are cytochrome P450 oxidases?
they are enzymes that are encoded by a family of genes and are responsible for metabolising many common drugs - there are many members of the gene family and are polymorphic
140
what is CVS?
chorionic villus sampling is an invasive method for obtaining tissue of foetal genotype for prenatal diagnostic testing - the alternative is amniocentesis
141
what is the grade of a tumour?
it is how aggressive a tumour is in terms of how closely it resembles its tissues of origin
142
what are teratomas?
malignant tumours of germ cells
143
what is a rhabdomyosarcoma?
it is a malignant tumour of the striated muscles
144
what is collagen?
it is the most abundant protein in the ECM and the target of MMPs
145
what is aflatoxin?
it is a potent carcinogen that is produced by a species of aspergillus growing on food
146
what happens over a lifetime with oestrogen?
exposure accumulates and plays an important role in the risk of developing breast cancer
147
what is the initial spread of carcinoma cell through?
lymphatic route
148
what is an angioma?
a benign tumour of the blood vessels
149
what is a lipsarcoma and a lipoma?
the malignant tumour of adipose tissue
| lipoma is benign
150
what is amplification/?
it is a common mechanism by which a proto-oncogene may become abnormally over expressed
151
what are promoters?
they are types of carcinogens that are effective at directly or indirectly stimulating the proliferation of cells
152
what staging method is used in colorectal cancer?
dukes staging method
153
what is the increased cellular feature in invasion?
motility
154
what is osteosarcoma?
malignant tumour of the bone
155
what is intravasation?
the stage at which the metastatic sequence allows access to vascular dissemination
156
what is meningioma?
benign disease of the meninges
157
what is stage?
it is the extent to which a tumour has spread
158
what site of tumours is usually associated with the condition XC?
the skin
159
in TMN, what do N and M stand for?
```
N = nodes
M = metastasis
```
160
what is multiple myeloma?
a malignant disease of the bone marrow
