Update on Monogenic Diabetes

Transcription

1 Update on Monogenic Diabetes Sung-Hoon Kim, M.D., Ph.D. Department of Medicine, Cheil General Hospital & Women s Healthcare Center, Kwandong University College of Medicine

2 Monogenic diabetes single gene mutations by β-cell function or IR 1-2% of diabetes, frequently misdiagnosed Atypical presentation for type 1 or 2 diabetes Autosomal dominant (or maternally inherited mitochondrial disorders) family Hx a/w deafness in mitochondrial diabetes Fat loss in lipodystrophy Diabetes diagnosed within the first 6 months of life

3 Contents Clinical issues in MODY Identification of MODY genes: past & present MODY in Korea Future directions

4 Maturity Onset Diabetes of the Young (MODY) First described in 1960s as: Non-insulin dependent diabetes Dominant pattern of inheritance Diagnosed before age 25

5 The RW pedigree Fajans SS and Bell GI. Diabetes Care 2011;34:

6 Genetic causes of MODY ( I ) MODY1 20q12 HNF-4a MODY2 7p15 Glucokinase MODY3 12q24 HNF-1a MODY4 13q12 IDX1/IPF1 MODY5 17q12 HNF-1b MODY6 2q32 NEUROD1

7 Genetic causes of MODY ( II ) MODY7 2p25 KLF11 MODY8 9q34 CEL MODY9 7q32 PAX4 MODY10 11p15 INS MODY11 8p23 BLK MODY12 MODY13 11p15 11p15 ABCC8 KCNJ11 MODYX??

8 Glucokinase and transcription factor MODY ( I )

9 Glucokinase and transcription factor MODY ( II )

10 Why diagnose MODY? 1. changes treatment

11 SU sensitivity in HNF1A-MODY Pearson et al. Lancet 2003

12 Why diagnose MODY? 1. changes treatment 2. informs prognosis 3. involves the whole family

13 Misdiagnosis Diagnosis is challenging due to overlap in clinical features with common forms of diabetes ~ 50% of HNF1A-MODY do not meet classical MODY criteria Clinicians have a reluctance to question original diagnostic label

14 Tools to differentiate MODY from common forms of diabetes MODY vs Type 1 diabetes Presence of C-peptide indicating endogneous insulin secretion (-> MODY) Presence of β-cell antibodies (-> T1DM) MODY vs Type 2 diabetes Presence of insulin restistance (-> T2DM) Relatively young age of diagnosis (-> MODY)

15 Clinical strategies of MODY Genetic testing and diagnosis, and prognosis Genetically susceptible subjects: counseling for periodic evaluation of glucose tolerance at a young age Normoglycemia beginning at the time of appearance of metabolic abnormalities can prevent complications

16 Identification of MODY genes: past and present

17 Why undertake gene mapping? Early identification of people at risk Better understanding of the pathophysiology Discovery of new drugs Tailored treatment programs

18 Identification of MODY11 (BLK)

19 Joslin MODY Families (Mean Age at Dx 35 yrs) Number of families Examined members Members with diabetes Members with IGT or GDM Average number of examined individuals with diabetes per family (3-17)

20 45y Diet 35y Oral 32y Ins 10y Ins 22y Ins 21y Oral 20y Diet 14y Ins 37y Diet 15y Diet 12y Ins 9y Ins 14y Ins

21 Characteristics of MODY subjects Age (yrs) Age at Diagnosis (yrs) Percent IBW (%) Treatment of diabetes (%) Insulin Oral Agents Diet

22 HNF-1a Mutations in Joslin MODY families Exon Dimerization and DNA binding E24fsdelGA L44fsdelC L107R A116V R130W Q146K H147R E240Q R272H Transactivation P291fsdelC P291fsinsC P291fsinsC P379fsdelCT A443fsdelCA Klupa et al., Diabetes Care 2002

23 Delta insulin (uu/ml) Insulin Secretion in MODY Families 180 HNF-1a mutations hr Glucose (mg/dl)

24 Delta insulin (uu/ml) Delta insulin (uu/ml) Insulin Secretion in MODYX Families 180 HNF-1a mutations 180 MODYX hr Glucose (mg/dl) hr Glucose (mg/dl)

25 Candidate genes involved in insulin action Insulin-receptor dependent pathways IRS-2 IRS-4 Grb10 GLUT 4 trafficking pathway VAMP2 VAMP3 SYN4 SNAP23 NSF negative negative negative negative negative negative negative negative Adipokines/Inflammation Adiponectin Resistin IKKb Common forms of insulin-resistance negative negative

26 Genome Screen 400 microsatellite markers (1 marker every 10 cm) Each marker tracks the surrounding genomic region Determine whether any genomic region is linked with the disease (LOD score = log 10 of the odds for linkage) Narrow the linked region and identify positional candidate genes

27 MODYX subjects for genome screen Total Families (n) Minority Families (n) Total Individuals (n) Affected individuals (n) Age at Dx (yrs) IGT/GDM (%) Percent IBW (%) Treatment Diet only (%) Oral agents (%) Insulin (%) 21 6 (2 H, 3 AA, 1 PI) ± ±

28 Microsatellites Genotyping 377 highly informative polymorphic markers Average spacing: 9.3 cm Average marker heterozygosity: 0.76 NHLBI Mammalian Genotyping Service at the Marshfield Institute

29 Linkage Analysis Parametric vs. nonparametric Two-point vs. multipoint Homogeneity vs. heterogeneity - LOD score Z( ) = log 10 L ( ) L (0.5) - HLOD = log 10 L (a, ) L (a =1, = 0.5)

30 First-pass linkage analysis

31 LOD Multipoint analysis of Chr 8 2 HLOD NP LOD cm

32 decode - Iceland Newest Linkage Map - 5,136 microsatellite markers, 869 individual, 1257 meioses - Average map resolution ~ 1 cm article A high-resolution recombination map of the human genome Augustine Kong, Daniel F. Gudbjartsson, Jesus Sainz, Gudrun M. Jonsdottir, Sigurjon A. Gudjonsson, Bjorgvin Richardsson, Sigrun Sigurdardottir, John Barnard, Bjorn Hallbeck, Gisli Masson, Adam Shlien,Stefan T. Palsson, Michael L. Frigge, Thorgeir E. Thorgeirsson, Jeffrey R. Gulcher & Kari Stefansson Nat Genet 31: , 2002

33 Comparison of the Marshfield and decode maps at 8p23 Marker Marshfield (cm) Decode (cm) Golden Path (Mb) D8S262 D8S518 D8S1742 D8S277 D8S561 D8S1706 D8S1825 D8S503 D8S516 D8S1721 D8S376 D8S265 D8S1695 D8S1759 D8S1130 D8S552 D8S1106 D8S1754 D8S GAP GAP

34 8p Inversion Polymorphism D8S1706 D8S503 D8S265 D8S1130 D8S552 tel cen REP 4 Mb REP D8S1706 D8S1130 D8S265 D8S503 D8S552 tel cen REP 4 Mb REP

35 Two-point linkage analysis at 8p23 Position Parametric Nonparametric Marker M D HLOD p LOD p D8S D8S D8S D8S x10-4 D8S D8S D8S x10-5 D8S x x10-4 GATA151F

36 Individual family LOD scores at D8S1130 Family LOD Race/Ethnic group A B C D E F G H I J K L M N O P Q R S T U Caucasian Caucasian Caucasian African-American Caucasian African-American Hispanic Caucasian Caucasian Hispanic Pacific Islander Caucasian Caucasian Caucasian Caucasian Caucasian African-American Caucasian Caucasian Caucasian Caucasian

37 A B D8S1706 D8S503 D8S1721 D8S265 D8S1130 tel Polymorphic Inversion cen REPD 90J21 80B8 REPP 1 Mb C D

38 D8S262 D8S518 D8S1742 D8S1706 D8S503 D8S1721 D8S265 D8S1130 GATA151F02 D8S1731 D8S262 D8S518 D8S1742 D8S1706 D8S1130 D8S265 D8S1721 D8S503 GATA151F02 D8S1731 A Critical interval at 8p23 Family 2.7 Mb LOD max F F B Family LOD max F

39 Summary We have identified a new form of MODY (MODYX) characterized by insulin-resistance rather than a pure insulin secretion defect. About 25% of these forms may be due to a gene placed on 2q37. This gene does not seem to correspond to calpain 10. In another 30% of families, diabetes is linked to a gene on 8p23. Through the analysis of recombination events, we were able to narrow the critical interval at this location to ~2.7 Mb.

40 Diabetes 2004;53:

41 Genes in the critical interval at 8p23

42 Resequencing of the 8p23-linked interval

43

44 Cosegregation of mutations at the 8p23 and MODY in 3 families

45

46 BLK as a positional candidate gene for the 8p23 MODY locus

47 Effect of noncoding mutations at the BLK locus on promoter activity in vitro

48 Modulation of β-cell function by BLK

49 Proc Natl Acad Sci U S A Aug 25;106(34):

50 Next Generation Sequencing Mardis ER, Annu. Rev. Genomics Hum. Genet 2008

51 Illumina HiSeq2000

52 PLoS ONE 2012

53

54 Prevalence of MODY in Korea Author Year Gene Methods Subjects Finding Journal Lee HJ 2001 HNF-1a SSCP 69 Early Onset T2DM 1/69 (1.5%) Syn Mutation Acta Diabetol Kim KA 2003 HNF-1a Sanger Sequencing 16 Early Onset T2DM 1/16 (6.25%) Nonsyn Mutation (R263L) Diabetologia Choi IK 2004 HNF-1a DNA Chip 17 MODY 1/22 (4.5%) Promoter Polymorphism, Nonsegregating Korean J Pediatr Hwang JS 2006 HNF-4a, GCK, HNF-1a Sanger Sequencing 23 MODY, 17 Early Onset T2DM 2/40 (5%) HNF-1a (P393fsdelC, Promoter) 1/40 (2.5%) GCK (R191W) 1/40 (2.5%) HNF-4a (T130I, polymorphism) Diabetes Res Clin Pract Lim DM 2008 HNF-1a DNA Chip 25 Early Onset T2DM 1/25 (4%) Promoter Polymorphism Korean J Intern Med Total 3/172 (1.7%)

55 MODY3 in Korean women with GDM

56 Gestational Diabetes Mellitus (GDM) Glucose intolerance with onset or first recognition during pregnancy Mostly caused by insulin resistance and ß-cell dysfunction Autoimmune or monogenic

57 Objectives Investigate whether MODY3 gene mutations are present in Korean women with GDM Evaluate clinical characteristics of GDM women with MODY3 gene mutations

58 HNF-1α Gene Human Chromosome : 12q24 LOC TCF1 (HNF-1α) OASL LOC C12orf43 Primer P

59 Subjects : 96 GDM women with a family history of DM Methods : Genotype Analysis Subjects and Methods Hydra II DNA 40ng Dry 384 well -plate PCR product Template : 0.5ul Big Dye 1 μl Primer 0.5 5X Buffer 0.5 μl DW : Total 5 μl Sequencing data analysis using Phrep/Phrap/Consed package and polyphred ABI 3730 Sequencing analysis Sequencing PCR

60 Clinical characteristics of women with GDM GDM women Number 96 Age at diagnosis (years) 33 ± 3.9 Pre-pregnancy BMI (kg/m 2 ) 25 ± g OGTT 0 hour (mg/dl) 93 ± 13 1 hour 189 ± 23 2 hour 178 ± 24 3 hour 147 ± 26 Fasting insulin (µ U/mL) ± 9.32 HOMA-IR 3.53 ± 2.48 HOMA-B ± Insulin therapy, n (%) 49 (51) Data are means ± SD

61 HNF-1α gene mutations : 5/96 (5.2%) SNP Functional locations of SNP Promoter known -124G>C 5 UTR new -23C>G Exon 4 new 833G>A(Arg278Gln) new 923C>T(Pro300Pro) Exon 6 new IVS5+106A>G

62 69 53 OAD OAD OAD INS INS Currant age Age at diagnosis Treatment Diabetes Mellitus Normal GDM (Diet: Diet therapy, OAD: oral antidiabetics, INS: Insulin therapy)

63 Conclusions We have found the existence of MODY3 as well as novel HNF-1α gene mutations in Korean women with GDM. Further studies to screen HNF-1α gene mutations in other family members and to identify whether other subtypes of MODY can contribute GDM are needed.

64 Whole Exome Sequencing in GDM Women

65 Future directions Establishment of a nationwide MODY registry Molecular genetics laboratory in Korea New MODY genes: Whole genome (or exome) sequencing

66 Acknowledgments Joslin Diabetes Center Alessandro Doria Maciej Borowiec Chong W. Liew Xiaowei Ma Tonino Ercolino Christine Powers Aviva Bashan Andrzej Krolewski James Warram David Poznik John Rogus Susan Bonner-Weir Arun Sharma Rohit N. Kulkarni University of Virginia Stephen Rich Josyf Mychaleckyj Columbia University Joseph Terwilliger Cheil General Hospital Hun-Sung Kim Sun-Hee Hwang KNIH Jong-Young Lee Seoul National University Hospital Soo Heon Kwak All members of the MODY families!