The DNA sequencer will see you now: lessons from Diabetes

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1 The DNA sequencer will see you now: lessons from Diabetes Professor Andrew Hattersley University of Exeter Medical School, Exeter, UK

2 Who should make treatment decisions in diabetes? OR Diabetologist Sequencer

3 Can we improve on the present simple approach to diabetes treatment based on severity? Blood glucose Treatment Nil Diet Exercise Tablets Insulin Can we tailor the treatment to the cause not the severity? Precision Medicine - the tailoring of medical treatment to the individual characteristics of the patient. Precision Diabetes - the tailoring of diabetes treatment to the individual characteristics of the patient especially the genetic cause of their diabetes

4 Precision Medicine: Genetics in Cancer Treatment Gefitinib response & Non-small-cell lung cancer Probability of PFS % Non-small-cell lung cancer activating somatic mutation in Epidermal Growth Factor Receptor (EGFR) Increases proliferation and metastasis Gefitinib targets and blocks the activity of the EGFR-TK EGFR mutation status predicts response Gefitinib EGFR M+ (n=132) Gefitinib EGFR M- (n=91) Carboplatin / paclitaxel Time from randomisation (months) Lynch et al NEJM 2009 Mok et al NEJM 2009 Sequence EGFR tumour prior to therapeutic decisions in NSCLC 4

5 Using genetic information to understand the cause of diabetes Type 1 diabetes genetic susceptibility Type 2 diabetes genetic susceptibility Monogenic diabetes genetic cause In monogenic diabetes 1 in 3 billion bases changed results in diabetes Clinical features Molecular genetic testing Diagnosis of specific monogenic subtype Pathophysiology Treatment

6 Maturity-onset diabetes of the young (MODY): in the pre-genetic era Early diagnosis of diabetes (<25) Non insulin-dependent diabetes Autosomal dominant inheritance Tattersall (QJM 1974)

7 Maturity-onset diabetes of the young (MODY): in the post genetic era MODY 22% Glucokinase 66% Transcription factors <1% Insulin <1% SUR1 11% MODY x 61% HNF1A 4% HNF4A 2% HNF1B <1% IPF1 <1% CEL

8 The Exeter Monogenic Diabetes team established 1995 Multi-disciplinary from beginning Sian Ellard - Clinical scientist Tim Fraying Research Scientist Maggie Shepherd Diabetes nurse Andrew Hattersley Diabetologist Integrated NHS and University from beginning

9 Liam incidental raised blood sugar Liam: Diagnosed age 6 yr Mother (diet treated T2D) found raised glucose 12mmol/l No symptoms Fasting glucose 6.2 mmol/l HbA1c 6.5% Clinical diagnosis Incidental hyperglycaemia probable early T1D. Insulin treatment Glucokinase mutation identified Review: Recognition and management of glucokinase Chakera et al Diabetes Care 2015

10 Glucokinase the pancreatic glucose sensor Glucose K ATP Channel sulphonylureas depolarisation Ca 2+ Voltage dependent Ca 2+ Channel L type GLUT 2 K + Glucokinase Glucose 6 P ATP MgADP [Ca 2+ ]i Insulin Metabolism Glucokinase mutations cause MODY (Froguel et al Nature 1992; Hattersley et al Lancet 1992) Nucleus Prevalence 1 in 1000 population (Chakera, Dunn et al Diabetes Care 2014)

11 Glucokinase - all patient have similar mildly raised fasting blood glucose values Fasting plasma glucose (mmol/l) mg/dl mg/dl HbA1c %, 38-58mmol/mol Paediatric incidental hyperglycaemia or T1D FPG 5.5-9mmol Gestational diabetes Age (years) Type 2 diabetes or prediabetes European MODY Consortium (n =242) Stride et al Diabetologia 2002 Steele et al PloS One 2013 Glucokinase Normal

12 Glucokinase patients do not respond to treatment and do not need treatment HbA1c % Cross sectional No Treatment 631 (n=799) OHA or Insulin 168 Nephropathy Longitudinal OHA or Insulin (n=16) Off Treatment Glucose is regulated at raised level Does not respond to treatment 31% Proteinuria Patients lifetime slight rise in blood sugar does not cause complications 1% 2% Microalbuminuria GCK n=98 Control n=89 YT2D n=80 Stride et al Diabetologia 2014 Steele, Shields et al JAMA 2014

13 1 patient: 2 possible outcomes GCK diagnosed No treatment No follow-up HbA1c 6.5% GCK not diagnosed Clinical diagnosis T1D GAD /IA2 negative Insulin pump and carbohydrate counting 3 monthly clinics HbA1c 6.5%

14 Peter Type 1 diabetes with diabetic parent 15 yr old boy Diagnosed with diabetes age 13 rpg 21mmol/l BMI 19 kg/m 2 Treated with 4x/day insulin HbA1c 8.2% Father Type 1 Diabetes

15 Family history of diabetes Autosomal dominant Type 1 and Type 2 HNF1A MODY

16 Large pharmacogenetics differences seen! HNF1A MODY sensitive to Sulphonylurea tablets 4x greater than in Type 2 Diabetes HbA1c % SU stopped Met started Years from Diagnosis SU started Met stopped Pearson et al Diabetic Medicine Type 2 HNF1a MODY Type 2 HNF1a MODY 0 Change in fasting plasma glucose with treatment (mmol/l) Metformin -4-5 Gliclazide Pearson et al Lancet 2003

17 Making a genetic diagnosis improves treatment HNF1A mutation diagnosed Peter stopped insulin better glucose control on half sulphonylurea tablet All family transferred to sulphonylurea tablets (3 stopping insulin) with improved control

18 In MODY genetic subtype determines clinical picture and treatment response MODY 22% Glucokinase 61% HNF1A 66% Transcription factors 4% HNF4A 2% HNF1B <1% IPF1 <1% CEL <1% NeuroD1 <1% Insulin 11% MODY x Treatment not needed Low dose SUs Insulin?too rare Insulin

19 Implementing Precision diabetes in MODY Relatively common 3% diabetes diagnosed < 30 years 40,000 cases in UK (UNITED Shields Pearson Hattersley Unpublished). Genetic diagnosis easily made technology improved available nationwide on NHS from Exeter lab Clear treatment recommendations when diagnosis confirmed best treatment known both outside and during pregnancy BUT MODY Patients are a minority - 97% don t have MODY > 95% misdiagnosed initially Type 1 or Type 2 On average 12 years from diabetes diagnosis to genetic diagnosis

20 Density Diagnosing MODY is difficult no single criteria no absolute cutoff Density Density Density Percentage Density Density Percentage Density Treatment Parent Affected with Diabetes T2D T1D GCK HNF1A/ HNF4A Age at in years Age Diagnosis yrs GCK HNF1A/ HNF4A HbA1c % T1D T2D GCK HNF1A/4A Type 1 Type 2 Treatment BMI (children converted to adult value) kg/m 2 GCK HNF1A/ T1D T2D GCK HNF1A/4A Type 1 Type 2 HNF4A Parental diabetes GCK T1D 1 HNF1A/ HNF4A T2D GCK HNF1A/ HNF4A T2D T1D HbA1c % BMI (children converted to adult value) kg/m 2 Age at Diagnosis in years BMI kg/m HbA1c % BMI (children converted to adult value) kg/m 2 HbA1c % Solution: combine all clinical information in single probabilistic model Shields et al Diabetologia 2012

21 Assisting MODY diagnosis with a Probability calculator Web- based App for mobile phones Diabetes Diagnostics App for Apple phones and Android Shields et al Diabetologia 2012

22 MODY testing is increasingly impacting on clinical care throughout the world More patients correctly diagnosed Routine NHS test 47 UK patients diagnosed ,621 UK patients diagnosed 2016 More patients now on correct treatment due to testing >50% change treatment after diagnosis Total UK referrals Genetic Diagnosis Testing available worldwide for MODY

23 Lilly - insulin-dependent diabetes at 3 months Diagnosed 3 months very ill Presented with Diabetic Ketoacidosis glucose 54 mmol/l Diagnosed Type 1 diabetes Treated with 4 insulin injections/day then insulin pump No insulin production Glucose very variable parents tested 8-10 times/day Diabetes diagnosed before 6 months is Neonatal Diabetes (monogenic) not Type 1 diabetes

24 Gene discovery can suggest possible treatment K ATP channel in neonatal diabetes 80% spontaneous Anna Gloyn 01H) ISPAD 22 (R201H) BR1 (R201H) ISPAD 25 (V59G) ATP II:3 NN I:1 NN p II:1 NM I:2 NN Gloyn et al NEJM 04 p I:1 NM II:1 NM I:2 NN Fran Ashcroft II:2 Fran NM Ashcroft I:1 na p d.14mo II:1 NM wild type I:2 na R201H mutation

25 One Patients with a Kir6.2 mutation had been treated with Sulphonylureas for 46 years Tolbutamide since diagnosis at 3 months At 46 years Fasting glucose 6.2 mmol/l C peptide 613 pmol/l Insulin Treated Insulin Treated

26 Patients with Kir6.2 mutations can transfer from insulin to sulphonylureas 18 Start sulphonylurea Blood glucose mmol/l HbA1c % Pal Njolstad 4 2 Sulphonylurea dose (mg/day) Insulin dose (U/day) Time (days after start of sulphonylurea treatment) 0 Sagen et al Diabetes 04

27 HbA1c Massive impact: 90% stop insulin, Glycaemic control is improved in all patients who stop insulin P < Ewan Pearson % 6.4% Michel Polak Pål Njølstad 4 On insulin On sulphonylurea Pearson et al NEJM 2006

28 Glucose values fluctuate less as well as being lower Insulin pump 7.5 mg Glibenclamide Zung et al JCEM 04

29 Rapid impact of precision diabetes on medical practice for K ATP neonatal diabetes Easier - clear single referral guideline (diagnosed < 6 months), clear diagnostic procedure clearly better treatment International guidelines changed <2 years after gene discovery Genetic testing required rapidly all patients diabetes < 6 months. Many countries now > 80% neonatal diabetes genetically tested Needed to remove barriers - lack of labs worldwide - cost of testing

30 Free rapid testing worldwide for Neonatal diabetes Ireland (14) (diagnosis < 6 months) funding Wellcome Trust ) UK (264) Belgium (10) France (5) Canada (41) USA (84) Puerto Rico (5) Trinidad & Tobago (2) Mexico (3) Guatemala (3) Honduras (6) Costa Rica (5) Venezuela (19) Ecuador (1) Netherlands (32) Colombia (7) Germany (95) Switzerland (3) Peru (4) Chile (15) Spain (3) Portugal (3) Denmark (4) Sweden (26) Poland (36) Tunisia (1) Morocco (9) Libya (6) Nigeria (2) Brazil (7) Argentina (27) Austria (12) Croatia (5) Bosnia (2) Czech Republic (12) Finland (2) Latvia (4) Slovakia (8) Oman (13) Indonesia (1) Kuwait (15) Bahrain (2) UAE (14) Saudi Arabia (45) Israel (14) Cyprus (2) Kenya (2) Turkey (128) Egypt (15) Sudan (10) Mauritius (1) Macedonia (2) Serbia (6) South Africa (32) Australia (37) Hungary (6) Romania (5) Bulgaria (7) Russia (2) Pakistan (10) India (121) Bangladesh (13) New Zealand (17) 1737 probands from 87 countries ( Iran (2) Kazakhstan (3) Iraq (1) Sri Lanka (6) Jordan (22) Georgia (1) Syria (1) Qatar (2) Kosovo (1) Greece(6) Ukraine (18) Lebanon (3) Korea (1) Japan (4) China (14) Vietnam (43) Thailand (9) Philippines (2) Singapore (7) Malaysia (15)

31 Can Precision diabetes be applied to Classification of Type 1 and Type 2 diabetes Cause Clinical Pathophysiology Type 1 Autoimmune Young and slim Total insulin deficiency Type 2 Non-Autoimmune Old and obese Reduced insulin secretion and action Initial Treatment Insulin & diet Diet/Tablets No endogenous insulin Need endogenous insulin Need to get the classification correct to give correct treatment For treatment endogenous insulin secretion (c-peptide) matters

32 Why we need Precision Diabetes for Classification of Type 1/Type 2 diabetes Mr yr UK Caucasian Factory Worker Thirsty drinking Coca Cola Slightly dehydrated BMI 33 kg/m 2 Glucose 33 mmol/l Ketones + Diagnosis? Treatment?

33 Why we need Precision Diabetes for Classification of Type 1/Type 2 diabetes Theresa 56 yrs (2012) weight loss, large urine volumes, increased drinking Diabetes diagnosed Classified Type 2 Diabetes treatment diet & exercise initially no response increasing numbers & types of tablets no response Re-classified as Type 1 (?autoantibody positive) started insulin rapidly improved Now insulin 4 x /day Wrong classification results in wrong treatment Classification Errors common especially if diagnosed years (7-14%) 56% diagnosed T1D >35yrs had Type 2 diabetes (Hope Diabetic Medicine 2016) Uncertain how common T1D is over 30 Clinical features? Treatment? Antibodies?

34 T1D why do we get it wrong in adults? Usually use Clinical Criteria +/- autoantibodies Clinical Criteria Broad imprecise guidance only (ADA,EASD,WHO) T1D: diagnosed young, slim, DKA presentation No cut offs defined against future absolute insulin deficiency Evidence base weak Systematic review: Only 10 studies clinical features v C peptide outcome Favoured age of diagnosis (<35yr) over BMI ( Shields et al BMJ Open 2015) Autoantibodies Assays not standardised > 50% UK labs measure rodent ICA! Prospective studies almost entirely children Not routinely measured in adults

35 Recognising Type 1 diabetes in elderly population Why GAD antibodies are not ideal % Positive GAD Auto-antibodies Specificity 97.5% Sensitivity 66% 70% 2.5% Controls Type 1 Patients tested alters interpretation < 20 years 95% T1D Positive predictive value 99.6% Specific test false positives rare (0.4%) > 40 years - 5% T1D Positive predictive value 60% Non specific false positives common (40%) If you diagnose T1D in adults using GAD - 40% will have T2D Therefore will be a mixture of Type 1 and Type 2

36 Can we use polygenic risk to help diagnose T1D/T2D accurately?

37 Type 1 Genetic Risk Score Measure of an individuals susceptibility to T1D 30 T1D associated SNPS Sum of risk-increasing alleles weighted by risk Measure T1D genetic susceptibility High score likely to be T1D 50 th centile 5 th Centile Low score - unlikely to be T1D Type 2 (WTCCC) n=1914 Type 1 (WTCCC) n=1938 Oram et al Diabetes Care 2016

38 Measuring Type 1 diabetes in a population How much excess diabetes occurs in people genetically susceptible to T1D and what is its characteristics? TYPE 1 DIABETES TYPE 2 DIABETES TYPE 2 DIABETES 50% population Not T1D susceptible (low T1D-GRS) 50% population T1D Susceptible (High T1D-GRS) 120,000 UK Caucasians UK Biobank data on diabetes and full genetic analysis

39 Number of new cases per population Type 1 diabetes : not just children & young adults constant incidence across first 6 decades of life Type 2 diabetes Type 1 diabetes Age of diagnosis Thomas, Oram, Weedon, Hattersley unpublished

40 Features of genetically identified Type 1 diabetes diagnosis yrs compared to Type 2 T1D T2D n=215 n=4120 Slimmer BMI 26.2 v 32.6 kgm -2 n=170 n=247 Usually on insulin by 1 yr 79% v 6% All on insulin ultimately 100% v 16% Admitted hospital 12% v 0% with DKA Characteristics and treatment needs are very similar to Type 1 diabetes < 30 years Thomas, Oram, Weedon, Hattersley unpublished

41 Precision diagnosis of Type 1 diabetes in adults use clinical, autoantibodies and T1D genetics Best individual diagnosis uses quantitative information not cut offs AND combines BMI, age diagnosis, autoantibodies, and T1D-GRS AgeD BMI All combined AUC 0.85 AUC 0.87 T1D-GRS AAbs AUC 0.98 AUC 0.87 AUC patients diagnosed yrs (classification difficult 21% T1D) Predict insulin deficiency needing insulin within 3 years with near 100% accuracy Oram et al Diabetes Care 2016

42 Using genetics in diabetes Precision Diabetes is a reality now Defining the genetic cause of an individual patient s diabetes can make diagnosis & improve that patient s treatment Polygenic risk can improve diagnosis but will need to be integrated with other risk factors Implementation of the science into clinical care may be harder than the science!

43 Who should make treatment decisions in diabetes? AND Diabetologist Sequencer

44 The Exeter Diabetes Research Team Gene discovery: Sian Ellard, Sarah Flanagan, Mike Weedon, Elisa De Franco, Anna Gloyn Hana Lango-Allen, Kevin Colclough, Richard Caswell, Jayne Houghton, Anne-Marie Patch Tim Frayling, Mike Bulman Annet Damhuis, Andrew Parrish Clinical: Post gene discovery: Maggie Shepherd, Tim McDonald, Richard Oram, Angus Jones, Ali Chakera, Ewan Pearson, Oscar Rubio-Cabezas, Rachel Besser, Pam Bowman, Katherine Owen, Bev Shields,, Anna Steele, Susie Hammersley, Gill Spyer, Kash Patel, Noel Morgan