Familial Hypercholesterolemia Honors Genetics 2006

Gel Interpretation  Measure the distance from the well to the bands( DNA fragments in the marker)  Graph using the marker sizes for Lambda Hind III  Interpolate the sizes of the bands for the patients, Normal and FHC control to verify your visual observations and impressions

Hypercholesterolemia Gel Results N FH C marke r

Gel Interpreation  Patient 1 – Homozygous recessive – both copies of the normal LDLR receptor  Patient 2 – Heterozygous for the LDLR receeptor  Patient 3- Homozygous dominant for the LDLR receptor – The most severe form of the disease

What is cholesterol??  Cholesterol is one of the body's fats (lipids). Cholesterol and another lipid, triglyceride, are important building blocks in the structure of cells and are also used in making hormones and producing energy.  To some extent, the cholesterol level in blood depends on what you eat but it is mainly dependent on how the body makes cholesterol in the liver.

Cholesterol and the Steroid Rings

Desirable cholesterol levels  Desirable — Less than 200 mg/dL Borderline high risk — 200–239 mg/dL High risk — 240 mg/dL and over  If your total cholesterol is less than 200 mg/dL, your heart attack risk is relatively low, unless you have other risk factors. Even with a low risk, it's still smart to eat foods low in saturated fat and cholesterol, and also get plenty of physical activity. Have your cholesterol levels measured every five years — or more often if you're a man over 45 or a woman over 55

Low density lipoproteins  This is sometimes called “ bad “ cholesterol  the blood, and the cholesterol from LDL is the main source of damaging buildup and blockage in the arteries.  Thus, the more LDL-cholesterol you have in your blood, the greater your risk of heart disease. If you have heart disease or are at high risk for developing it and your LDL is 100 mg/dLor higher, your cholesterol may well be too high for you.

High Density Lipoproteins  HDL carry cholesterol in the blood from other parts of the body back to the liver, which leads to its removal from the body.  So HDL help keep cholesterol from building up in the walls of the arteries. If your level of HDL- cholesterol is below 40 mg/dL, you are at substantially higher risk for heart disease.  The higher your HDL-cholesterol, the better. The average HDL- cholesterol for men is about 45 mg/dL, and for women it is about 55 mg/dL.

Tests in the Lipid Profile  Total Cholesterol  HDL Cholesterol  LDL Cholesterol  VLDL Cholesterol  Triglycerides  Apolipoprotein A1Extended Lipid Profile.  Apolipoprotein B  Lipoprotein(a)

 Before withdrawing blood for lipid profile :-  a hours fasting sample is required.  b. Individuals should have been on their usual diet.

Case History referene - OMIM  European populations.  Like the French Canadians, the South Afrikaners appear to have a unique form of mutation in the LDLR gene consistent with founder effect (Brink et al., 1987). Because of the presumed role of founder effect on the high frequency of familial hypercholesterolemia in South Africa, it is not surprising that Kotze et al. (1987) found a predominance of 2 haplotypes in 27 informative families with FH. In a study of homozygotes from the Afrikaner population in South Africa, Leitersdorf et al. (1989) found that 2 mutations account for more than 95% of the mutant LDL receptor genes. Both mutations were basepair substitutions that resulted in a single amino acid change and both could be detected readily with PCR and restriction analysis. The findings were considered consistent with the high frequency of FH being due to founder effect.

Chromosome –  Start: 11,061,132 bp from pterEnd: 11,105,490 bp from pterSize: 44,358 bases

Gene Expression

SNP – Single nucleotide polymorphism  CTATGACACCA/GTCATCAGCAG  rs rs  F (+)CCACACGAAGA/GCCTGCAAGGC rs5928 rs5928  F (+)AAGAACTGGCA/GGCTTAAGAAC 1R/Q ns 2A:0.01MN  rs5930 rs5930  F,C,A (+)TCATCAGCAGA/GGACATCCAGG 1R/R syn 3A:0.37MN EA  rs5927 rs5927  F,C,A (+)CAACCACCCGA/GCCTGTTCCCG 1R/R syn 2A:0.08MN EA 1620  rs5925 rs5925  F,C,A (+)AGGATATGGTC/TCTCTTCCACA 1V/V syn 3C:0.18MN EA  rs688 rs688  F,C,A (+)TCGATGTCAAC/TGGGGGCAACC 1N/N syn 1T:0.32MN 126  rs5929 rs5929  F,C (+)GGGGAACTCCC/TGCCAAGATCA 1P/P syn 2T:0.04MN 310  rs rs  F,C (+)GTGGCCGCCTC/TTACTGGGTTG 1L/L syn  rs5933 rs5933  F,C (+)GCAATAGAATC/TTACTGGTCTG

HGMD  /mg/search/ html /mg/search/ html /mg/search/ html  This data base shows all the different mutations  For Familial hypercholesterolemia there are 806 mutations  457 mutations are missense and nonsense

Substitution mutations  GGG-AGG Gly-Arg Hypercholesterolaemia  GCG-GAG Ala-Glu Hypercholesterolaemia  CTC-CCC Leu-Pro Hypercholesterolaemia  cGAG-TAG Glu-Term Hypercholesterolaemia

RCSB – The LDLR receptor

Sequence for LDLR protein  MGPWGWKLRW TVALLLAAAG TAVGDRCERN EFQCQDGKCI SYKWVCDGSA ECQDGSDESQ ETCLSVTCKS GDFSCGGRVN RCIPQFWRCD GQVDCDNGSD EQGCPPKTCS QDEFRCHDGK CISRQFVCDS DRDCLDGSDE ASCPVLTCGP ASFQCNSSTC IPQLWACDND PDCEDGSDEW PQRCRGLYVF QGDSSPCSAF EFHCLSGECI HSSWRCDGGP DCKDKSDEEN CAVATCRPDE FQCSDGNCIH GSRQCDREYD CKDMSDEVGC VNVTLCEGPN KFKCHSGECI TLDKVCNMAR DCRDWSDEPI KECGTNECLD NNGGCSHVCN DLKIGYECLC PDGFQLVAQR RCEDIDECQD PDTCSQLCVN LEGGYKCQCE EGFQLDPHTK ACKAVGSIAY LFFTNRHEVR KMTLDRSEYT SLIPNLRNVV ALDTEVASNR IYWSDLSQRM ICSTQLDRAH GVSSYDTVIS RDIQAPDGLA VDWIHSNIYW TDSVLGTVSV ADTKGVKRKT LFRENGSKPR AIVVDPVHGF MYWTDWGTPA KIKKGGLNGV DIYSLVTENI QWPNGITLDL LSGRLYWVDS KLHSISSIDV NGGNRKTILE DEKRLAHPFS LAVFEDKVFW TDIINEAIFS ANRLTGSDVN LLAENLLSPE DMVLFHNLTQ PRGVNWCERT TLSNGGCQYL CLPAPQINPH SPKFTCACPD GMLLARDMRS CLTEAEAAVA TQETSTVRLK VSSTAVRTQH TTTRPVPDTS RLPGATPGLT TVEIVTMSHQ ALGDVAGRGN EKKPSSVRAL SIVLPIVLLV FLCLGVFLLW KNWRLKNINS INFDNPVYQK TTEDEVHICH NQDGYSYPSR QMVSLEDDVA

References  sources:  Genetic association of low density lipoprotein receptor and Alzheimer's disease. (2005) Genetic association of low density lipoprotein receptor and Alzheimer's disease. Genetic association of low density lipoprotein receptor and Alzheimer's disease.  The modular adaptor protein ARH is required for low density lipoprotein (LDL)binding and internalization but not for LDL receptor clustering in coated pits. (2004) The modular adaptor protein ARH is required for low density lipoprotein (LDL)binding and internalization but not for LDL receptor clustering in coated pits. The modular adaptor protein ARH is required for low density lipoprotein (LDL)binding and internalization but not for LDL receptor clustering in coated pits.  Molecular characterization of familial hypercholesterolemia in Spain: identificationof 39 novel and 77 recurrent mutations in LDLR. (2004) Molecular characterization of familial hypercholesterolemia in Spain: identificationof 39 novel and 77 recurrent mutations in LDLR. Molecular characterization of familial hypercholesterolemia in Spain: identificationof 39 novel and 77 recurrent mutations in LDLR.  Harmful effects of increased LDLR expression in micewith human APOE*4 butnot APOE*3. (2004) Harmful effects of increased LDLR expression in micewith human APOE*4 butnot APOE*3. Harmful effects of increased LDLR expression in micewith human APOE*4 butnot APOE*3.  Estrogen receptor-alpha and Sp1 interact in the induction of the low densitylipoprotein- receptor. (2003) Estrogen receptor-alpha and Sp1 interact in the induction of the low densitylipoprotein- receptor. Estrogen receptor-alpha and Sp1 interact in the induction of the low densitylipoprotein- receptor.  Generation and initial analysis of more than 15,000 full-length human and mouse cDNA Generation and initial analysis of more than 15,000 full-length human and mouse cDNA Generation and initial analysis of more than 15,000 full-length human and mouse cDNA

References  Comparison of apolipoprotein B metabolism in familial defective apolipoproteinB and heterogeneous familial hypercholesterolemia. (2002) Comparison of apolipoprotein B metabolism in familial defective apolipoproteinB and heterogeneous familial hypercholesterolemia. Comparison of apolipoprotein B metabolism in familial defective apolipoproteinB and heterogeneous familial hypercholesterolemia.  Molecular basis of familial hypercholesterolemia in Brazil: Identificationof seven novel LDLR gene mutations. (2002) Molecular basis of familial hypercholesterolemia in Brazil: Identificationof seven novel LDLR gene mutations. Molecular basis of familial hypercholesterolemia in Brazil: Identificationof seven novel LDLR gene mutations.  Identification of Egr1 as the oncostatin M- induced transcription activatorthat binds to sterol-independent regulatory element of human LDL receptor promoter. (2002) Identification of Egr1 as the oncostatin M- induced transcription activatorthat binds to sterol-independent regulatory element of human LDL receptor promoter. Identification of Egr1 as the oncostatin M- induced transcription activatorthat binds to sterol-independent regulatory element of human LDL receptor promoter.  Sequencing of the coding exons of the LRP1 and LDLR genes on individual DNA samples reveals novel mutations in both genes. (2001) Sequencing of the coding exons of the LRP1 and LDLR genes on individual DNA samples reveals novel mutations in both genes. Sequencing of the coding exons of the LRP1 and LDLR genes on individual DNA samples reveals novel mutations in both genes.