患儿，女，以“显著矮身材”为首发症状。母孕期超声检查多次提示四肢偏短。患儿表现为毛发细软、稀疏、色浅，四肢偏短，影像学检查提示骨骺改变。全外显子基因测序检测阴性。进一步行Sanger测序检测到线粒体处理RNA的内切酶复合物RNA组分（RNA component of mitochondrial RNA processing endoribonuclease，RMRP）基因，一个非编码RNA基因，存在g.181G→A/g.255C→T复合杂合变异，g.255C→T为新发现的突变。软骨-毛发发育不全临床表现复杂，典型症状有助于诊断该病；特别是全外显子基因测序检测阴性时，应考虑该病并进行鉴别诊断；必要时完善一代测序（Sanger法）检测，以帮助确诊、评估预后及产前诊断。新发现的变异丰富了该病的基因谱。

The main symptom of a female pediatric patient was severely short stature. Ultrasound examinations during pregnancy showed that the limbs were short. The patient was characterized by sparse, fine, and silky hair and prenatal onset of disproportionate short-limb short stature. Radiographic findings showed metaphyseal dysplasia with epiphyseal in terminal femur and proximal tibia. Whole exon sequencing of DNA from peripheral blood was negative. However, sanger sequencing confirmed that the patient had carried g.181G→A/g.255C→T compound heterozygous variants of RNA component of mitochondrial RNA processing endoribonuclease (RMRP) gene, which is a non-coding RNA in human genome. The g.255C→T was a novel mutation. The clinical manifestations of cartilage-hair hypoplasia (CHH) are complex and typical symptoms can help diagnose the disease. CHH should be considered as a differential disease when whole exon sequencing was negative in patients with suspected bone disease. Sanger sequencing test can help confirm the diagnosis, contributing to evaluating the prognosis and prenatal diagnosis. Discovery of the novel variants has enriched the variant spectrum of CHH.