Pulmonary alveolar microlithiasis is a disorder in which many tiny fragments (microliths) of calcium phosphate gradually accumulate in alveoli. Loss of function mutations in the gene SLC34A2 coding for the sodium phosphate co-transporter (NaPi-IIb) are responsible for genetic forms of alveolar microlithiasis. We now report a consanguineous Italian family from Calabria with two affected members segregating alveolar microlithiasis in a recessive fashion. We describe, for the first time, a novel loss of function mutation in the gene coding for NaPi-IIb. A careful description of the clinical phenotype is provided together with technical details for direct sequencing of the gene.
Keywords: AD, Autosomic dominant; AR, Autosomic recessive; CH, Compound heterozygous; Hsa, Homo sapiens; NaPi-IIb; OMIM, Online Mendelian inheritance in man; PAM, Pulmonar alveolar microlithiasis; PAS, Periodic acid-Schiff; Pulmonary alveolar microlithiasis; SLC34A2.