Exome sequencing reveals a novel homozygous mutation in ACP33 gene in the first Italian family with SPG21
SPG21, also known as Mast Syndrome (MIM 248900), is an ultra-rare autosomal recessive complicated form of hereditary spastic paraparesis (HSP) characterized by slowly progressive spasticity with dementia, occurring with high frequency in the Old Order Amish . After the first Amish family, a single Japanese family with two affected members was reported . Here we describe an Italian family with a single affected member carrying a novel homozygous single base deletion in the acidic cluster protein 33, ACP33 gene (SPG21) and presenting with a phenotype characterized by cognitive decline prevailing on the spastic paraparesis component.
Difficulties at school and motor problems were noted in the patient since childhood. By the early 20s, mental function declined with progressive speech limitation, as well as evidence of clear executive dysfunctions and subtle personality disturbances. At neurological examination at 39 years of age, a spastic paraparesis was evident, with...
The Authors wish to thank the patient and his family for participating to the study. This work was supported by the Italian Ministry of health under the frame of E-Rare-2, the ERA-Net for Research on Rare Diseases Grant NEUROLIPID, by the 5XMille Funds and by Grant No. RC 2014-2017 to MTB.
Compliance with ethical standards
Conflicts of interest
All authors declare not to have any conflict of interest with the study and manuscript.
The study was conducted according to the ethical standards stated in the declaration of Helsinki.
Patients and patient's family were informed about the intention to publish the study and provided a written informed consent.
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