IFNA1 and microcephalic primordial dwarfism: Except for common diagnostic tools that are used in AGS recognition (IFN-α level in cerebrospinal fluid, IFN-1 signature in blood, and clinical genome sequencing) there are specific rare cellular tests that seem to be promising in differential diagnosis for other related conditions (for example, Cockayne and Seckel syndromes) [14,15].