Clinical characterization of PLAG1-related Silver-Russell syndrome:A clinical report

Background: Silver-Russell syndrome (SRS) is a rare genetic disorder that is mainly associated with prenatal and postnatal growth retardation. Loss of methylation on chromosome 11p15 and maternal uniparental disomy on chromosome 7 (upd(7)mat) are two common causes, accounting for approximately 50% and 10% of all patients, respectively. Pathogenic variants of genes, such as HMGA2, IGF2, CDKN1C, and PLAG1, have also been detected in patients with SRS. So far, SRS caused by PLAG1 alterations have only been described in two sporadic cases and three families.Patient presentation: The genetic and clinical manifestations of SRS in a patient carrying a novel variant of PLAG1 were reported and these results were compared with those of five previously reported cases. Trio-based wholeexome sequencing revealed a heterozygous variation in PLAG1 (NM_002655.3: c.131del; p.(Asn44Thrfs*6)) in an infant girl with clinical suspicion of SRS. Familial studies confirmed that the mutation was inherited from her father. As seen in previously reported cases, the patient presented with prenatal and postnatal growth retardation, relative macrocephaly at birth, prominent forehead during infancy, and triangular face. However, no clinical characteristics such as feeding difficulties, hypothyroidism, or psychomotor and speech delay.Conclusions: This study identified the sixth documented case of PLAG1 variants leading to SRS and expanded our knowledge of the molecular spectrum of SRS phenotypes.