When do we need to suspect maturity onset diabetes of the young in patients with type 2 diabetes mellitus?

ABSTRACT Objetivo: Maturity onset diabetes of the young (MODY) patients have clinical heterogeneity as shown by many studies. Thus, often it is misdiagnosed to type 1 or type 2 diabetes(T2DM). The aim of this study is to evaluate MODY mutations in adult T2DM patients suspicious in terms of MODY, and to show clinical and laboratory differences between these two situations. Subjects and methods: In this study, we analyzed 72 type 2 diabetic patients and their relatives (35F/37M) who had been suspected for MODY and referred to genetic department for mutation analysis. The gene mutations for MODY have been assessed in the laboratory of Marmara University genetics. Totally 67 (32F/35M; median age 36.1) diabetic patients were analyzed for 7 MODY mutations. Twelve patients who have uncertain mutation (VUS) were excluded from study for further evaluation. MODY(+) (n:30) patients and T2DM patients (n:25) were compared for clinical and laboratory parameters. Results: In MODY(+) subjects, mutations in GCK (MODY 2) (n:12; 40%) were the most common followed by HNF4A (MODY 1) (n:4; 13.3%). Diabetes diagnosis age was younger in MODY(+) group but not statistically significant. Sixty-six percent of MODY(+) subjects had diabetes history at 3-consecutive generations in their family compared with 28% of T2DM patients statistically significant (p:0.006). Gender, BMI, C-peptide, HbA1c, lipid parameters, creatinine, GFR, microalbuminuria, vitamin D and calcium were not statistically different between the groups. Conclusion: According to present study results, MODY mutation positivity is most probable in young autoantibody (-) diabetic patients diagnosed before 30 years of age, who have first degree family history of diabetes.

HNF1A-AS1 inhibits proliferation, migration and invasion of IL-6-induced hemangioma endothelial cells by targeting miR-363-3p / 中华医学遗传学杂志

OBJECTIVE@#To explore the effect of HNF1A-AS1 on the proliferation, migration and invasion of IL-6-induced hemangioendothelial cells (HemEC) and possible mechanism.@*METHODS@#RT-qPCR was used to detect the expression level of HNF1A-AS1 and miR-363-3p in the tumor tissue and adjacent normal skin tissue from 35 patients with hemangioma. Pearson correlation was used to analyze the correlation between the expression of HNF1A-AS1 and miR-363-3p in tumor tissues. HemEC were isolated and cultured in vitro.Dual luciferase reporter gene experiment was used to study the regulatory effect between HNF1A-AS1 and miR-363-3p. IL-6 was added to HemEC transfected with si-NC, si-HNF1A-AS1, si-HNF1A-AS1 and anti-miR-NC, or si-HNF1A-AS1 and anti-miR-363-3p, respectively. CCK-8 method and clone formation experiment were used to detect cell proliferation in each group. Transwell method was used to detect cell migration and invasion in each group. Western blotting was used to detect the expression of Ki67, MMP-2 and MMP-9 proteins in each group.@*RESULTS@#Compared with normal skin tissues, the expression of IL-6 mRNA in hemangioma tissues was increased (P<0.05), and the expression of IL-6 mRNA in the proliferative phase was lower than that in the degenerative phase (P<0.05). Expression of HNF1A-AS1 in hemangioma tissue was increased (P<0.05), while that of miR-363-3p was decreased (P<0.05), and the two were negatively correlated (r=-0.758, P<0.05). HNF1A-AS1 down-regulated the expression of miR-363-3p in HemEC.IL-6 promoted the expression of HNF1A-AS1, OD value, number of colonies, number of migration and invasion of HemEC cells, and the expression of Ki67, MMP-2 and MMP-9proteins (P<0.05), while reduced the expression of miR-363-3p (P<0.05). Down-regulating si-HNF1A-AS1 reduced the IL-6-induced HemEC cell OD value, colony numbers, migration and invasion and the expression of Ki67, MMP-2 and MMP-9 proteins (P<0.05). Down-regulating miR-363-3p attenuated the inhibitory effect of down-regulating si-HNF1A-AS1 on the proliferation, migration and invasion of HemEC cells induced by IL-6 (P<0.05).@*CONCLUSION@#Expression of HNF1A-AS1 is increased in hemangioma tissues. Down-regulating HNF1A-AS1 may inhibit proliferation, migration and invasion of IL-6-induced hemangioma endothelial cells by targeted up-regulation of miR-363-3p.

MODY probability calculator for GCK and HNF1A screening in a multiethnic background population

ABSTRACT Objective We aimed to identify the frequency of monogenic diabetes, which is poorly studied in multiethnic populations, due to GCK or HNF1A mutations in patients with suggestive clinical characteristics from the Brazilian population, as well as investigate if the MODY probability calculator (MPC) could help patients with their selection. Subjects and methods Inclusion criteria were patients with DM diagnosed before 35 years; body mass index < 30 kg/m2; negative autoantibodies; and family history of DM in two or more generations. We sequenced HNF1A in 27 patients and GCK in seven subjects with asymptomatic mild fasting hyperglycemia. In addition, we calculated MODY probability with MPC. Results We identified 11 mutations in 34 patients (32.3%). We found three novel mutations. In the GCK group, six cases had mutations (85.7%), and their MODY probability on MPC was higher than 50%. In the HNF1A group, five of 27 individuals had mutations (18.5%). The MPC was higher than 75% in 11 subjects (including all five cases with HNF1A mutations). Conclusion Approximately one third of the studied patients have GCK or HNF1A mutations. Inclusion criteria included efficiency in detecting patients with GCK mutations but not for HNF1A mutations (< 20%). MPC was helpful in narrowing the number of candidates for HNF1A screening.

More than kin, less than kind: one family and the many faces of diabetes in youth

SUMMARY Identification of the correct etiology of diabetes brings important implications for clinical management. In this report, we describe a case of a 4-year old asymptomatic girl with diabetes since age 2, along with several individuals in her family with different etiologies for hyperglycemia identified in youth. Genetic analyses were made by Sanger sequencing, laboratory measurements included HbA1c, lipid profile, fasting C-peptide, pancreatic auto-antibodies (glutamic acid decarboxylase [GAD], Islet Antigen 2 [IA-2], and anti-insulin). We found a Gly178Ala substitution in exon 5 of GCK gene in three individuals co-segregating with diabetes, and type 1 diabetes was identified in two other individuals based on clinical and laboratory data. One individual with previous gestational diabetes and other with prediabetes were also described. We discuss difficulties in defining etiology of hyperglycemia in youth in clinical practice, especially monogenic forms of diabetes, in spite of the availability of several genetic, laboratory, and clinical tools.

HNF1α mutations are present in half of clinically defined MODY patients in South-Brazilian individuals / Mutações HNF1α estão presentes na metade dos pacientes da região sul do Brasil clinicamente diagnosticados com MODY

Maturity-onset diabetes of the young (MODY) is a monogenic form of diabetes mellitus characterized by autosomal dominant inheritance, early age of onset, and pancreatic beta cell dysfunction. Heterozygous mutations in at least seven genes can cause MODY. In the present study we investigated the relative prevalence of GCK (glucokinase) and HNF1α (hepatocyte nuclear factor 1α) mutations, the more frequent causes of MODY, in 13 South-Brazilian families with multiple cases of diabetes consistent with MODY. Heterozygous variants in GCK and HNF1α genes were observed respectively in one (7.7 percent), and six (46.2 percent) families. The six HNF1α variants are likely to cause diabetes in the families where they were observed. However, we could not ascertain whether the GCK Gly117Ser variant found in one family is a causal mutation. In conclusion, we have confirmed in a South-Brazilian population that HNF1α mutations are a common cause of monogenic diabetes in adults selected with strict clinical diagnostic criteria.

O maturity-onset diabetes of the young (MODY) é uma forma monogênica de diabetes melito caracterizada por herança autossômica dominante, de instalação precoce, como disfunção da célula beta pancreática. Mutações heterozigotas em pelo menos sete genes causam MODY. No presente estudo, investigamos a prevalência relativa das mutações da GCK (glucokinase) e HNF1α (hepatocyte nuclear factor 1α), as causas mais freqüentes de MODY, em 13 famílias sul-brasileiras com múltiplos casos de diabetes consistentes com MODY. Variantes heterozigotas nos genes da GCK e HNF1α foram observadas, respectivamente, em uma (7,7 por cento) e em seis (46,2 por cento) famílias. As seis variantes do HNF1α provavelmente causaram o diabetes nas famílias nas quais foram observadas. No entanto, não se pode afirmar que a variante GCK Gly117Ser encontrada em uma família seja a mutação causal. Em conclusão, confirmamos que, em uma população do sul do Brasil, as mutações HNF1α são uma causa comum de diabetes monogênico em adultos selecionados com critérios clínicos diagnósticos estritos.

Hepatocyte nuclear factor 1-alpha mutation in normal glucose-tolerant subjects and early-onset type 2 diabetic patients

BACKGROUND/AIMS: The prevalence of diabetes in Korea is reported to be approximately 10%, but cases of maturity-onset diabetes of the young (MODY) are rare in Korea. A diagnostic technique for autosomal dominant MODY is being actively sought. In this regard, we used a DNA chip to investigate the frequency of mutations of the MODY3 gene (hepatocyte nuclear factor-1alpha) in Korean patients with early-onset type 2 diabetes. METHODS: The genomic DNA of 30 normal individuals [age, 24.9+/-8.6 years] and 25 patients with early-onset type 2 diabetes (age, 27+/-5.9 years) was extracted, and the MODY3 gene was amplified. The amplified DNA was hybridized onto a MODY3 chip, which has oligonucleotides of 15-25 bases, representing wild-type and mutant MODY3 sequences in both forward and reverse orientations, immobilized on its surface. RESULTS: Among the normal subjects, there was no mutation of MODY3. Among those with early-onset type 2 diabetes, there was one case of MODY3 mutation. CONCLUSIONS: Our results indicate that MODY3 mutations are not rare in Korean early-onset type 2 diabetes patients in Korea and suggest that MODY3 mutations in patients with early-onset type 2 diabetes need to be further evaluated.