Common Diseases to Chromosomal/genetic Defects Flashcards
AML (Acute myeloblastic leukaemia)
Chromosome 5: deletion >> poor prognosis
Chromosome 7: deletion >> poor prognosis
t(9: 22): Philadelphia chromosome >> poor prognosis
t(8:21) >> good prognosis
t(15:17) = (PML:RAR-alpha fushion >> APML >> good prognosis
ALL (Acute lymphoblastic leukaemia)
Most common: t(12: 21) = (TEL: AML1) >> good prognosis
Chromosome 9p: deletion >> good prognosis
Trisomy 4, 10, 17 >> good prognosis
Hyperdiploidy >> good prognosis
t(9:22) [Philadelphia chromosome] >> poor prognosis
t(4:11) >> poor prognosis
CML (Chronic myeloid leukaemia)
t(9:22) = Philadelphia chromosome >> Poor prognosis
(ABL) Abelson proto-oncogene: location 34 of long arm (q) of chromosome 9 >> is translocated to >> BCR (Breakpoint cluster region) gene: location 11 of long arm(q) of chromosome 22
BCR: ABL encodes for tyrosine kinase
CLL (Chronic lymphocytic leukaemia)
Chromosome 13 (long arm, q) >> deletion (around 50%)
Chromosome 17 (short arm, p) >> full/part deletion (around 5-10%)
Burkitt’s lymphoma
t(8: 14) =
MYC oncogene on chromosome 8 >> is translocated to >> an immunoglobulin (Ig) gene on chromosome 14
Mantle cell lymphoma
t (11;14) =
Deregulation of the cyclin D1 (BCL-1) gene
Follicular adenoma
t(14; 18) =
Deregulation of BCL-2 gene (anti-apoptotic gene)
Haemophilia A, B
‘Flip tip inversion’ in the factor VIII gene in the X chromosome (factor IX gene for type B)
Von Willibrand disease
Chromosome 12 >> tip of short arm (p): VWF gene mutation
Hereditary Haemorrhagic Telangiectasia (HHT) type 1
Chromosome 9;
Gene: ENG;
Protein: Endoglin
Hereditary Haemorrhagic Telangiectasia (HHT) type 2
Chromosome 12;
Gene: ACVRL1/ALK-1;
Protein: ALK-1
Hereditary Haemorrhagic Telangiectasia (HHT) type 3
Chromosome 5;
Gene: RASA1
Hereditary Haemorrhagic Telangiectasia (HHT) type 4
Chromosome 7
Gene: unknown
Hereditary Haemorrhagic Telangiectasia (HHT) type 5
Chromosome 10:
Gene: GDF2
Juvenile Hereditary Haemorrhagic Telangiectasia (JHHT)
Chromosome 18;
Gene SMAD4/ MADH4
PRV (polycythaemia rubra vera)
In 95% cases, Chromosome 9(p, short arm): JAK2 (V617F) mutation
Essential thrombocythaemia
In 50% cases, Chromosome 9(p, short arm): JAK2 (V617F) mutation
Myelofibrosis
In 50% cases, Chromosome 9(p, short arm): JAK2 (V617F) mutation
Activated protein C resistance (Factor V leiden disease)
Chromosome 1: FVL gene mutation (single point mutation)
Antithrombin III deficiency
Chromosome 1 (q, long arm) ; Gene: AT3 gene (AKA SERPINC gene)
Protein C deficiency
Chromosome 2 (q. long arm)
Gene: PROC gene mutation
Myeloproliferative HES (Hypereosinophilic syndrome) or Eosinophilic leukaemia
FIP1L1-PDFRA genotype
Haemochromatosis
Chromosome: 6
Gene: C282Y HFE mutation
Also, H63D
G6PD deficiency
Chromosome X
Gene: G6PD
Hereditary spherocytosis
For Northern European:
- Chromosome 1: Gene SPTA1: Encodes: Spectrin- (alpha)
- Chromosome 8: Gene ANK1: Encodes: Ankyrin
Less common:
- Actin
- Protein 4.2 (Japanese)
Sickle cell disease/anaemia
Chromosome: 11 (p, short arm) location 6
Gene: HBB >> encodes beta-globin chain
Alpha thalassemia
Chromosome 16
Gene: HBA1 & HBA2
So, Each chromosome has 2 gene >> 2 + 2 >> 4 gene in chromosome pair >> encodes alpha-globin chains/alpha subunits
Beta thalassemia
Chromosome: 11
Gene: HBB
So, Each chromosome has 1 gene >> 1 + 1 >> 2 genes in chromosome pair >> encodes beta-globin chains/beta subunits
Von Hippel Lindau syndrome
Chromosome 3 (short arm, p)
Gene: VHL
Friedreich’s ataxia
Chromosome 9
Gene: FXN (X25)
Protein: Frataxin
Tuberous Sclerosis (TS)
Chromosome 9; Gene: TSC1
Chromosome 16: Gene: TSC2
Neurofibromatosis
Type 1: Chromosome 17: Gene: NF1
Type 2: Chromosome 22: Gene: NF2
(Recall, Neurofibromatosis has 17 characters, so NF1 has 17 no chromosome; NF2 has all 2)
Ataxia telangiectasia
Chromosome 11
Gene: ATM gene
Encodes for: DNA repair enzymes
Alzheimer’s disease
Only 5% is inherited as autosomal dominant
Chromosome 1: Gene: PSEN2; encodes: Presenilin 2
Chromosome 14; Gene: PSEN1; encodes: Presenilin 1
Chromosome 17: Gene: MAPT; encodes tau protein
Chromosome 19; Gene: APOE e4 (Apoprotein allele e4); encodes cholesterol transport protein
Chromosome 21: Gene: APP: encodes: Amyloid precursor protein
Huntington’s disease
Chromosome 4
Gene: HTT (Huntingtin) (= IT15: Interesting type 15) gene
Triplet repeats: CAG
(Recall, CAGe has 4 letters)
Wilson’s disease
Chromosome: 13
Gene: ATP7B
Encodes for: Copper-transporting ATPase 2
Myotonic dystrophy (Dystrophia myotonica)
Type 1: Chromosome: 19; Gene: DMPK; triplet repeat: CTG
Type 2: Chromosome 3: Gene: ZNF9, repeat expansion (4base pair sequence CCTG)
DMPK encodes for Dystrophia myotonica protein kinase
ZNF9 encodes for Zinc finger protein 9
Pendred’s syndrome
Chromosome 7
Gene: PDS gene (formerly called), SLC26A4 (now called)
Pseudohypoparathyroidism
Chromosome: 20
Gene: GNAS
Encodes for: Gs-alpha (alpha subunit of stimulatory G protein)
Pseudopseudohypoparathyroidism
Chromosome: 20
Gene: GNAS
Encodes for: Gs-alpha (alpha subunit of stimulatory G protein)
(Same as pseudohypoparathyroidism)
Nephrogenic diabetes insipidus
For X-linked recessive (mainly): Chromosome X; Gene: AVPR 2; Encodes for: Arginin-vasopressin receptor-2
For Autosomal recessive/dominant: Chromosome 12; Gene AQP2; Encodes for Aquaporin-2
Type 1 Diabetes mellitus
Polygenic
(Antibody to Glutamate Acid Decarboxylase: GAD)
MODY type 1
Chromosome 20
Gene: HNF-4 alpha (hepatocyte nuclear factor 4 alpha)
Encodes: hepatocyte nuclear factor 4 (a transcription factor)
MODY type 2
Chromosome 7
Gene: GCK gene (Glucokinase gene)
Encodes: Glucokinase
MODY type 3
Chromosome 12
Gene: HNF-1 alpha
Encodes for: Hepatocyte nuclear factor 1 (A transcription factor)
(60% cases of MODY is MODY 3, 20% is MODY 2, <10% is MODY 1)
Liddle’s syndrome
Chromosome 16
Gene: SCCNN 1A, 1B, 1G
Encodes for: ENaC (Epithelial Na channel)
Gitelman’s syndrome
(Mostly)
Chromosome: 16
Gene: SLC12A3
Encodes for: Thiazide-sensitive sodium-chloride co-transporter
Familial Hyper-chylomicronaemia
(Type I dyslipidaemia/hyperlipoproteinaemia/hyperlipidaemia)
Chromosome 8
Gene: LPL
Familial hypercholesterolaemia
(Type IIA dyslipidaemia/hyperlipidaemia/hyperlipoproteinaemia)
Chromosome 19: Gene: LDLR (90% cases)
Chromosome 1: Gene: APOB
LDLR encodes LDL receptor protein (which normally removes LDL from circulation)
APOB encodes for Apolipoprotein B (part of LDL) that binds to receptor
(some more genetic mutations are involved but rare)
Familial combined hyperlipidaemia/hyperapobetalipoproteinaemia
(Type IIB Dyslipidaemia/Hyperlipoprotaeinemia/hyperlipidaemia)
Chromosome 19; Gene: ApoE
Chromosome 8; Gene: LPL & many others
Remnant hyperlipidaemia/Dysbetalipoproteinemia/Broad Beta disease
(Type III dyslipidaemia/hyperlipidaemia/hyperlipoproteinaemia)
Chromosome: 19
Gene: APOE-2
Encodes: Apo-lipoprotein E
Primary familial hypertriglyceridaemia
(Type IV dyslipidaemia/hyperlipidaemia/hyperlipoproteinaemia)
Polygenic
Chromosome 11; Gene: ApoA5 & many more
Familial mixed hyperlipidaemia
(Type V dyslipidaemia/hyperlipoproteinaemia/hyperlipidaemia)
Chromosome 11
Gene: APOA5
Autoimmune polyendocrinopathy syndrome (APS)
Type 1: (AKA MENDAC)
Chromosome 21
Gene: AIRE1
Type 2: Polygenic
(Type 1 is autosomal recessive, Type 2 is polygenic)
MEN type 1 (= Wermer syndrome)
(Multiple endocrine neoplasia type 1)
Chromosome 11
Gene: MEN1 gene (a tumour supressor gene)
MEN type IIa (= Sipple syndrome)
(Multiple Endocrine Neoplasia type 2a)
Chromosome: 10
Gene: RET oncogene
MEN type IIb
(Multiple Endocrine Neoplasia type 2b)
Chromosome: 10
Gene: RET oncogene
Androgen Insensitivity Syndrome (AIS)
Chromosome X
Gene: AR
Encodes for: Androgen receptor
(It has male genotype 46XY, but female phenotype; due resistance to androgen receptor)
(previously called testicular faminisation syndrome)
Familial glucocorticoid remediable aldosteronism (GRA) (= Familial hyperaldosteronism type 1)
Chromosome 8
Gene: CYP11B1 & CYP11B2
(unequal crossing over between these 2 genes result in chimeric gene)
Papillary thyroid carcinoma
Chromosome 1
Gene: Trk
Encodes for: Tyrosine kinase receptor
(Activation of tyrosine kinase receptor has a role in papillary thyroid carcinoma)
CAH (Congenital adrenal hyperplasia)
Chromosome 6
Gene: CYP21A2
Carney complex
Chromosome 17
Gene: PRKAR1 gene
Encodes for: protein kinase
Peutz-Jeghers syndrome
Chromosome 19
Gene: STK11 (also called LKB1)
Encodes: Serine threonine kinase
Sporadic colon cancer
>50% shows allelic loss APC gene on chromosome 5
Others:
Activation/mutation of K-ras oncogene on chromosome 12
Deletion of P53 on chromosome 17
Deletion of DCC gene on chromosome 18
(APC encodes Adenomatour polyposis coli protein has tumour supressor properties
K-ras= oncogene encodes K-ras protein, involed in cell signalling, converts GTP to GDP
P53 is a tumour supressor gene
DCC = Deleted in colorectal carcinoma)
HNPCC (Hereditary non-polyposis colorectal carcinoma)
More than 7 gene mutations are identified
The most common are:
hMLH1 gene on chromosome 3 (= MLH1)
hMSH2 gene on chromosome 2 (= MSH2)
hMSH6 gene on chromosome 2 (= MSH6)
they encode DNS mismatch repair proteins
FAP (Familial Adenomatous Polyposis)
Chromosome 5
Gene: APC mutation
(Adenomatous polyposis gene is a tumour supressor gene)
ZES (Zollinger Ellison syndrome)
30% is part of MEN type 1
So, in 30% cases,
Chromosome 11
Gene: MEN1 gene (a tumour supressor gene)
Carcinoma of pancreas
The most common: K-ras oncogene on chromosome 12
If associated with HNPCC >> MLH1 gene on chromosome 3
If associated with Peutz Jegher’s syndrome >> STK11 gene on chromosome 19
If associated with dysplastic naevi/melanoma >> CDKN2a gene on chromosome 19
Also, BRCA1, BRCA2, P53
If insulinoma of MEN1 >> MEN1 gene on chromosome 11
Cowden’s syndrome
Chromosome 10
Gene PTEN
Familial Juvenile polyposis
Chromosome 18: Gene: SMAD4
Chromosome 10: Gene: BMPR1A
Wilson’s disease
Chromosome 13
Gene: ATP7B
Encodes: Copper transporting ATPase 2
Gilbert’s syndrome
Chromosome 2
Gene: UGT1A1 gene
Encodes: UDP glucuronyl transferase
(so, deficiency of UDP glucuronyl transferase)
Dubin Johnson syndrome
Chromosome: 10
Gene: ABCC2
Encodes: MRP2 (Mutlidrug resistant protein 2)
(It is deficiency of cMOAT: canalicular multispecific organic anion transporter)
Rotor syndrome
Chromosome 12: SLCO1B1 & SLCO1B2
Crigler Najjar syndrome
Chromosome 2
Gene: UGT1A1 gene
Encodes: UDP glucuronyl transferase
ADPKD (Autosomal dominant polycystic kidney disease)
Type 1: Chromosome 16, Gene PKD1, encodes for polycystin-1
Type 2: Chromosome 4, Gene PKD2, encodes for polycystine-2
ARPKD (Autosomal Recessive Polycystic Kidney Disease)
Chromosome 6, Gene PKHD1, Encodes fibrocystin
Alport’s syndrome
Chromosome X
Gene: COL 4A5
Encodes: Type IV collagen
(resulting in abnormal glomerular basement membrane - GBM)
AR & AD: COL4A4 and COL4A3
Fanconi anaemia (syndrome)
Polygenic
Renal Tubular Acidosis (RTA) type 3 (Juvenile RTA)
Chromosome 8
Gene: CA II
Encodes: Carbonic Anhydrase 2
(So, carbonic anhydrase 2 deficiency)
Phenylketonuria (PKU)
Chromosome 12
Gene: PAH
Encodes: Phenyl-alanine hydroxylase
Cystinuria
Chromosome 2: Gene SLC3A1
Chromosome 9: Gene SLC7A9
Homocystinuria
Chromosome 21
Gene CBS
Encodes: Crystathione Beta-synthetase
Alkaptonuria
Chromosome 3
Gene HGD
Encodes for: Homogentisate 1,2-dioxygenase
(so, defect in this enzyme)
Bladder cancer
Chromosome 17p13.1, Gene P53 >> high grade bladder cancer
Chromosome 9p15 and 9p16 mutation >> low grade & superficial tumours
(Many other factor are associated with it)
Osteogenesis imperfecta
Chromosome 17; Gene COL1A1
Chromosome 7; Gene COL1A2
(For type 1 to type 4, common autosomal dominant types)
Lesch-Nyhan syndrome
Chromosome X (long arm, q26-26.3)
Gene: HPRT1
Enocodes for: Hypoxanthine Phosphoribosyltransferase
(This gene is involved in purine salvage pathway, so defect results in hyperuricemia/gout)
Ankylosing spondylitis
Its not a genetic disorder, but in some cases, present in family member/first degree relative >>
Gene: Polygenic
Associated with HLA-B27; All HLA is encoded by chromosome 6
Familial Mediterranean Fever (FMF)
(AKA recurrent polysclerositis)
Chromosome 16
Gene MEFV
Encodes for: protein pyrin
(PRotein pyrin is present in leukocytes, especially neutrophils & monocytes)
Congenital Long QT syndrome
(AKA inherited/familial)
For most common variant LQT1
Chomosome 11
Gene KCNQ1
(Other genotypes for other variants)
Genes coding for ion channel proteins
Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)
polygenic
Wolf-Parkinson White (WPW) syndrome
Chromosome: 7
Gene: PRKAG2
Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT)
Chromosome 1
Gene RYR2 (mainly & for AD)
Encodes Rynodine receptor (present in myocardium sarcoplasmic reticulum)
(Also many other genes)
Brugada syndrome
For the most common type ( = Brugada syndrome type 1)
Chromosome 3
Gene: SCN5a
Encodes for: Myocardial Na ion channel protein
HOCM (Hypertrophic Obstructive Cardiomyopathy)
Most important:
Chromosome 14: Gene: MYH7 > Encodes: Beta-myosin heavy chain
Chromosome 1: Gene: TNNT2 > Encodes: Troponin T
Chromosome 15: Gene: TPM1 > Encodes: Tropomyosin 1alpha/Alpha-tropomyosin
Other common:
Chromosome 11: Gene: MYBPC3 > Encodes: Myosin binding protein C
Chromosome 19: Gene: TNNI3 > Encodes: Troponin I
(Others are rare)
Inherited Dilated Cardiomyopathy (DCM)
Chromosome 5
Gene: SGCD
Cystic Fibrosis
Chromosome 7 (long arm, q); Region: Delta F508
Gene: CFTR
Encodes: cAMP regulated chloride channel
Delta F508 mutation = deletion of three nucleotides coding for phenylalanine residue
Hereditary breast cancer
Chromosome 17; Gene BRCA 1
Chromosome 13, Gene BRCA 2
P53 & others are less common
Hereditary ovarian cancer
Most common: Chromosome 17; Gene BRCA 1
2nd common: Chromosome 13, Gene BRCA 2
p53 & others are less common
Porphyria: Acute intermittent porphyria (AIP)
Chromosome 11
Gene HMBS
Porphyria: Familial, Porphyria cutanea tarda (PCT)
Chromosome 6; Gene HFE
Chromosome 1; Gene: UROD
(HFE is also a chromosome of haemochromatosis)
Porphyria: Variegate porphyria
Chromosome 6, Gene HFE
Chromosome 1, Gene PPOX
(HFE gene is also responsible for PCT & haemochromatosis)
Porphyria: Congenital Erythropoietic porphyria (CEP)
Chromosome 10
Gene: UROS
Abetalipoproteinaemia
Chromosome 4
Gene: MTTP
Lawrence-Moon-Biedl syndrome
Chromosome 19
Gene: PNPLA6
Retinitis pigmentosa
Polygenic
30% are AR: Chromosome 3: Gene: RHO > Encodes: rhodopsin
Other genes are X-linked, AR, AD
Vitamin D resistant Rickets
Chromosome X
Gene: PHEX
(Phosphate regulating gene with homology to endopeptidases)
Incontinentia Pigmenti (IP)
Chromosome X
Gene: NEMO
(NF kappa B essential modulator gene)
Periventricular nodular heteroptia
Chromosome X
Gene: FLNA
Encodes: Filamin A
Rett syndrome
Chromosome X
Gene; MeCP2
Encodes: Methyl CpG-binding protein 2
Noonan’s syndrome
Chromosome 12
Gene: PTPN11 (50% and most common)
Encodes: Protein tyrosine phosphatase non-receptor type 11
Also:Chromosome 15, Gene MAP2K1, Encodes mitogen-activated protein kinase kinase 1 (member of MAPK kinase pathway) & several others
Hereditary motor and sensory neuropathy (Charcot- Marie- Tooth disease)
For AD: Chromosome 17, Gene: PMP22, Encodes: Peripheral Myelin protein 22
For AD, AR, X-linked; other genes (polygenic)
Achondroplasia
Chromosome 4
Gene: FGFR 3
Encodes: Fibroblast Growth Factor Receptor 3
Pseudoxanthoma elasticum
Chromosome 16; Gene: ABCC2, XYLT1
Chromosome 17: Gene: XYLT2
Galactosaemia
Mainly,
Chromosome 9
Gene: GALT
Encodes: Galactose-1-phosphate uridyl transferase
(uridyl or uridylyl)