A new clinical entity in T704M mutation in periodic paralysis

Periodic paralyses (PPs) are a group of rare disorders characterized by episodic, sudden-onset, flaccid paralysis of skeletal muscles usually resulting in complete recovery after the attacks. PPs are caused by abnormal, mostly potassium-sensitive excitability of the muscle tissue. Hypokalemic and hyperkalemic periodic paralysis (HypoKPP and HyperKPP) have been described according to their characteristic phenotypes and the serum potassium level during the attacks of weakness. The T704M mutation on the SCN4A gene is the most common mutation in HyperKPP. Different mutations of the SCN4A gene have also been reported in some cases of HypoKPP. In this study, a large Turkish family carrying the T704M mutation on the SCN4A gene with HypoKPP disease was examined. A similar history was noted in a total of 17 subjects in the pedigree. SCN4A gene of the patients was sequenced with Sanger sequencing. In this study, this mutation was associated with a HypoKKP diagnosis for the first time in the literature. The symptoms of hallucination and diplopia seen in patients had also never been indicated in the literature before. This report expands the phenotypic variability of the T704M mutation, further confirming the lack of genotype-phenotype correlation in SCN4A mutations. (C) 2020 Elsevier Ltd. All rights reserved

Germline landscape of BRCAs by 7-site collaborations as a BRCA consortium in Turkey

BRCA1/2 mutations play a significant role in cancer pathogenesis and predisposition particularly in breast, ovarian and prostate cancers. Thus, germline analysis of BRCA1 and BRCA2 is essential for clinical management strategies aiming at the identification of recurrent and novel mutations that could be used as a first screening approach. We analyzed germline variants of BRCA1/2 genes for 2168 individuals who had cancer diagnosis or high risk assessment due to BRCAs related cancers, referred to 10 health care centers distributed across 7 regions covering the Turkish landscape. Overall, 68 and 157 distinct mutations were identified in BRCA1 and BRCA2, respectively. Twenty-two novel variants were reported from both genes while BRCA2 showed higher mutational heterogeneity. We herein report the collective data as BRCA Turkish consortium that confirm the molecular heterogeneity in BRCAs among Turkish population, and also as the first study presenting the both geographical, demographical and gene based landscape of all recurrent and novel mutations which some might be a founder effect in comparison to global databases. This wider perspective leads to the most accurate variant interpretations which pave the way for the more precise and efficient management affecting the clinical and molecular aspects