Hypotrichosis with juvenile macular dystrophy (HJMD or CDH3) is an extremely rare congenital disease characterized by sparse hair growth (hypotrichosis) from birth and progressive macular corneal dystrophy. Signs and symptoms Hair growth on the head is noticeably less full than normal, and the hairs are very weak; the rest of the body shows normal hair. The macular degeneration comes on slowly with deterioration of central vision, leading to a loss of reading ability. Those affected may otherwise develop in a completely healthy manner; life expectancy is normal. Cause Hypotrichosis with juvenile macular dystrophy is an autosomal recessive hereditary disease. It is caused by a combination of mutations (compound heterozygosity) in the CDH3 gene, which codes for Cadherin-3 (also known as P-Cadherin), a calcium-binding protein that is responsible for cellular adhesion in various tissues. Diagnosis The markedly anomalous hair growth should lead to a retinal examination by school entry at the latest, since weak vision will not necessarily be detected in the course of normal medical check-ups. Confirmation of a diagnosis, which is necessary for any future therapeutic options, is only possible by means of a molecular genetic diagnosis in the context of genetic counseling. Examination method The extent of retinal damage is assessed by fluorescent angiography, retinal scanning and optical coherence tomography; electrophysiological examinations such as electroretinography (ERG) or multifocal electroretinography (mfERG) may also be used. Differential diagnosis Anomalies of the hair shaft caused by ectodermal dysplasia should be ruled out. Mutations in the CDH3 gene can also appear in EEM syndrome. Treatment There is no treatment for the disorder. A number of studies are looking at gene therapy, exon skipping and CRISPR interference to offer hope for the future. Accurate determination through confirmed diagnosis of the genetic mutation that has occurred also offers potential approaches beyond gene replacement for a specific group, namely in the case of diagnosis of a so-called nonsense mutation, a mutation where a stop codon is produced by the changing of a single base in the DNA sequence. This results in premature termination of protein biosynthesis, resulting in a shortened and either functionless or function-impaired protein. In what is sometimes called "read-through therapy", translational skipping of the stop codon, resulting in a functional protein, can be induced by the introduction of specific substances. However, this approach is only conceivable in the case of narrowly circumscribed mutations, which cause differing diseases. Life planning A disease that