Inverted formin 2 mutations with variable expression in patients with sporadic and hereditary focal and segmental glomerulosclerosis.

Focal and segmental glomerulosclerosis (FSGS) is a major cause of end-stage kidney disease. Recent advances in molecular genetics show that defects in the podocyte play a major role in its pathogenesis and mutations in inverted formin 2 (INF2) cause autosomal dominant FSGS. In order to delineate the role of INF2 mutations in familial and sporadic FSGS, we sought to identify variants in a large cohort of patients with FSGS. A secondary objective was to define an approach for genetic screening in families with autosomal dominant disease. A total of 248 individuals were identified with FSGS, of whom 31 had idiopathic disease. The remaining patients clustered into 64 families encompassing 15 from autosomal recessive and 49 from autosomal dominant kindreds. There were missense mutations in 8 of the 49 families with autosomal dominant disease. Three of the detected variants were novel and all mutations were confined to exon 4 of INF2, a regulatory region responsible for 90% of all changes reported in FSGS due to INF2 mutations. Thus, in our series, INF2 mutations were responsible for 16% of all cases of autosomal dominant FSGS, with these mutations clustered in exon 4. Hence, screening for these mutations may represent a rapid, non-invasive and cost-effective method for the diagnosis of autosomal dominant FSGS.

Germline CEBPA mutation in familial acute myeloid leukemia.

Myeloid Neoplasms with germline predisposition become part of 2016 World Health Organization (WHO) classification of hematological malignancies since 2016. CCAAT/enhancer binding protein-alpha (CEBPA) is a myeloid transcription factor located in chromosome 19q. Acute myeloid leukemia (AML) with biallelic mutations of CEBPA AML with recurrent genetic abnormalities according to WHO classification. The inheritance of a germline CEBPA mutation predisposes to the development of AML with autosomal dominant inheritance. Familial CEBPA AML share characteristics with somatic CEBPA AML. However, a higher relapse incidence is reported. We present the case of a 46-years-old male with family history of acute leukemia who was diagnosed with single mutated CEBPA acute myeloid leukemia. The same mutation was found in two of his siblings. The clinical suspicion and proper diagnosis of familial cases is necessary, especially when a related allogenic transplant is indicated in order to select an adequate donor.