Hany Ummey, Watson Christopher M, Liu Lu, Nikolopoulos Georgios, Smith Claire E L, Poulter James A, Antanaviciute Agne, Rigby Alice, Balmer Richard, Brown Catriona J, Patel Anesha, de Camargo María Gabriela Acosta, Rodd Helen D, Moffat Michelle, Murillo Gina, Mudawi Amal, Jafri Hussain, Mighell Alan J, Inglehearn Chris F
Leeds Institute of Medical Research, University of Leeds, St. James's University Hospital, Leeds, UK.
North East and Yorkshire Genomic Laboratory Hub, Central Lab, St. James's University Hospital, Leeds, UK.
Hum Mutat. 2025 Jul 22;2025:8942542. doi: 10.1155/humu/8942542. eCollection 2025.
Amelogenesis is the process of tooth enamel formation, and genetic variants disrupting it cause the Mendelian inherited disorder amelogenesis imperfecta (AI). AI patients have weak, discoloured or brittle enamel, caused by reduced enamel quantity or mineralisation. AI can occur in isolation or, less commonly, as part of a syndrome. Pathogenic variants in at least 38 genes have been shown to cause AI. Current genetic screening studies typically use exome sequencing, but this is expensive and involves complex data analysis workflows. Target enrichment using smMIPs (single molecule molecular inversion probes) provides a flexible alternative, allowing the creation of a disease-specific reagent for low cost, robust, high-throughput screening. Here, we describe the development of an smMIP reagent targeting 19 genes implicated in isolated AI and assess its use in screening a cohort of 181 UK probands with nonsyndromic AI. While this was intended only as a prescreen to prioritise exome sequencing more efficiently, it nevertheless led to molecular diagnoses for 63 probands (35%). Cost per sample screened was approximately £40. Variants in three genes, , (both dominant) and (recessive), accounted for approximately half of solved cases. There is scope to further improve the smMIP reagent by adding additional probes targeting regions of low coverage or additional genes, including those involved in syndromic AI, as well as accommodating new information about the genetic basis of AI. The smMIP reagent provides a robust, flexible, high-throughput, low-cost approach to AI screening, and it is available as a resource to the international AI research community.
釉质形成是牙釉质形成的过程，破坏它的基因变异会导致孟德尔遗传性疾病釉质发育不全（AI）。AI患者的牙釉质薄弱、变色或易碎，这是由于牙釉质数量减少或矿化所致。AI可单独出现，或较少见地作为综合征的一部分出现。已证明至少38个基因中的致病变异可导致AI。目前的基因筛查研究通常使用外显子组测序，但这成本高昂且涉及复杂的数据分析流程。使用单分子分子倒置探针（smMIPs）进行靶向富集提供了一种灵活的替代方法，允许创建一种低成本、稳健、高通量筛查的疾病特异性试剂。在此，我们描述了一种针对19个与孤立性AI相关基因的smMIP试剂的开发，并评估了其在筛查181名英国非综合征性AI先证者队列中的应用。虽然这仅旨在作为一种预筛查，以便更有效地优先进行外显子组测序，但它仍导致63名先证者（35%）获得分子诊断。每个样本的筛查成本约为40英镑。三个基因（均为显性）和（隐性）中的变异约占已解决病例的一半。通过添加针对低覆盖区域的额外探针或其他基因（包括那些与综合征性AI相关的基因），以及纳入有关AI遗传基础的新信息，有进一步改进smMIP试剂的空间。该smMIP试剂为AI筛查提供了一种稳健、灵活、高通量、低成本的方法，并且作为一种资源可供国际AI研究界使用。
