Germline genetic variants in Turkish familial multiple myeloma/monoclonal gammopathy of undetermined significance cases.

Multiple myeloma (MM) is a haematological malignancy primarily affecting the elderly, with a striking male predilection and ethnic disparities in incidence. Familial predisposition to MM has long been recognized, but the genetic underpinnings remain elusive. This study aimed to investigate germline variants in Turkish families with recurrent MM cases. A total of 37 MM-affected families, comprising 77 individuals, were included. Targeted next-generation sequencing analysis yielded no previously reported rare variants. Whole exome sequencing analysis in 11 families identified rare disease-causing variants in various genes, some previously linked to familial MM and others not previously associated. Notably, genes involved in ubiquitination, V(D)J recombination and the PI3K/AKT/mTOR pathway were among those identified. Furthermore, a specific variant in BNIP1 (rs28199) was found in 13 patients across nine families, indicating its potential significance in MM pathogenesis. While this study sheds light on genetic variations in familial MM in Turkey, its limitations include sample size and the absence of in vivo investigations. In conclusion, familial MM likely involves a polygenic inheritance pattern with rare, disease-causing variants in various genes, emphasizing the need for international collaborative efforts to unravel the intricate genetic basis of MM and develop targeted therapies.