A novel KLF11 variant in a family with maturity-onset diabetes of the young

OBJECTIVE

The Krüppel-like factor 11 (KLF11) gene causes maturity-onset diabetes of the young 7 (MODY7). There are few reports on the clinical and functional characteristics of KLF11 mutations in patients with MODY7, making diagnosis and treatment complicated.

RESEARCH DESIGN AND METHODS

We report a novel KLF11 variant associated with MODY7 in a Chinese family. The proband had hyperglycemia at 9 years of age, and his mother had developed diabetes at age 28 years. Both required insulin injections from the initial phase of the disease. They were negative for islet cell autoantibodies and had normal fasting C-peptide levels. We observed changes in the levels of fasting blood glucose, C-peptide, and islet cell autoantibodies in the proband over 4.5 years.

RESULTS

Whole-exon sequencing was used to screen the proband and his family members for KLF11 variants. The heterozygous KLF11 variant (c.1045C>T, p. Pro349Ser) was identified in the proband, his mother, his maternal grandmother, and an elderly aunt, although the latter two individuals were unaffected. In silico analyses indicated that this variant involved a change in the amino acid side chain in the transcriptional regulatory domain 3. Luciferase reporter assays revealed that the variant had impaired insulin promoter regulation activity. Moreover, in vitro analyses showed that this variant impaired insulin secretion from pancreatic beta cells.

CONCLUSIONS

This study documents a novel heterozygous KLF11 variant (p. Pro349Ser) as a potential monogenic mutation associated with MODY7 in a family. This variant impairs insulin secretion from pancreatic beta cells, possibly by repressing insulin promoter regulation activity.

Maturity-onset Diabetes of the Young Type 7 (MODY7) and the Krüppellike Factor 11 Mutation (KLF11). A Review

INTRODUCTION

Maturity-onset diabetes of the young (MODY) is a rare disease due to a single gene mutation that affects several family members in most cases. The Krüppel-like factor 11 (KLF11) gene mutation is associated with decreased insulin sensitivity to high glucose levels. KLF 11 has been implicated in the pathogenesis of MODY type 7 but given its low prevalence, prolonged subclinical period, and the emergence of new information, doubts are raised about its association.

METHODS

A literature search of the PubMed, Scopus, and EBSCO databases was performed. The terms "Diabetes Mellitus, Type 2/genetics", "Mason-Type Diabetes" , "Maturity-Onset diabetes of the young", "KLF11 protein, human", and "Maturity-Onset Diabetes of the Young, Type 7" were used"., "Diagnosis" The search selection was not standardized.

RESULTS

The KLF1 mutation is rare and represents <1% of the mutations associated with monogenic diabetes. Its isolation in European family lines in the first studies and the emergence of new variants pose new diagnostic challenges. This article reviews the definition, epidemiology, pathophysiology, diagnosis, and treatment of MODY type 7.

CONCLUSION

MODY type 7 diabetes represents a rare form of monogenic diabetes with incomplete penetrance. Given its rarity, its association with impaired glucose metabolism has been questioned. Strict evaluation of glycemic control and the appearance of microvascular complications are key areas in the follow-up of patients diagnosed with MODY 7. More studies will be required to characterize the population with KLF11 mutation and clarify its correlation with MODY.

Novel gene mutation in maturity-onset diabetes of the young: A case report

BACKGROUND

Maturity-onset diabetes of the young (MODY) is the most common monogenic type of diabetes. Recently, 14 gene mutations have been found to be associated with MODY. In addition, the KLF11 gene mutation is the pathogenic gene of MODY7. To date, the clinical and functional characteristics of the novel KLF11 mutation c. G31A have not yet been reported.

CASE SUMMARY

We report of a 30-year-old male patient with a one-year history of nonketosis-prone diabetes and a 3-generation family history of diabetes. The patient was found to carry a KLF11 gene mutation. Therefore, the clinical data of family members were collected and investigated. A total of four members of the family were found to have heterozygous mutations in the KLF11 gene c. G31A, which resulted in a change in the corresponding amino acid p.D11N. Three patients had diabetes mellitus, and one patient had impaired glucose tolerance.

CONCLUSION

The heterozygous mutation of the KLF11 gene c.G31A (p. D11N) is a new mutation site of MODY7. Subsequently, the main treatment included dietary interventions and oral drugs.