To the Editor. Sweat duct proliferations and related cutaneous tumours pose a challenge for diagnosis and treatment due to the presence of multiple overlapping histopathological features (Schaller et al. 2010). In 1961 Nicolau and Balus described individuals with benign cutaneous lesions including atrophodermia vermiculata, multiple syringomata and milia which become known as Nicolau-Balus syndrome and was characterised by irregular distribution of elastin fibres (Nicolau and Balus 1961). A similar phenotype was later described as Rombo syndrome by Michaelsson et al (Michaelsson et al. 1981), with elastin distribution in these cases appearing like “swathes of steel wool” in some areas of the dermis (Van Steensel et al. 2001). In 2010, Schaller et al described several cases with the same abnormal elastin distribution, with the additional feature of sweat duct proliferations that appear morphologically similar to those found in microcystic adnexal carcinoma (MAC) patients, but (unlike MAC) were not invasive and did not require surgical resection (Schaller et al. 2010). In this study we describe five families with clinical and histopathological features that show similarities to Nicolau-Balus and Rombo syndromes with some cases also showing MAC-like ductal proliferations (figure S1). We provide evidence that these syndromes are caused by germline pathogenic variants in MYH9. Accordingly, we propose the term MALTA (MYH9 Associated eLasTin Aggregation) syndrome to reflect the common underlying genetic basis of this disease.