Female Samples
Fabry disease is X-linked but females can still be affected. There is overlap at the lower end of the α-galactosidase A activity reference range between affected and unaffected cases so a biomarker is also used. Samples from females only were sent to ARCHIMEDlife laboratories (Vienna, Austria) for assay of α-galactosidase A activity and Lyso-globotriaosylceramide (lyso-GL-3), a biomarker that is increased in Fabry disease, by Tandem mass spectrometry8. Results from the female samples showing either a low enzyme activity, increased lyso-GL-3 or both resulted in genetic sequence testing. α-galactosidase activity below the reference interval for females (1.2 – 50.0 µmol/l /hr) or Lyso-GL-3 above the reference limit (0-3.5ng/ml) were considered significant. (comment: ref interval for a gal enzyme activity analysed for the female samples at Archimed changed about the start of June 2019 to 2.8 - 50.0 umol/l/hr, as per letter issued, so if there are any samples that were sent for analysis after this timeframe the new range will have been used).