To report a case of autosomal recessive cutis laxa type 2A with novel retinal findings. Case report. A 22-year-old female patient presented with a long-standing history of reduced visual acuity in her right eye. She has generalized redundant skin, downslanting of palpebral fissures, and long philtrum. Ophthalmic examination showed ptosis in her right eye and visual acuity of 20/2000 in the right eye and 20/30p in the left eye. Funduscopic examination showed a round macular scar lesion in the right eye macula and a chorioretinal scar superonasally in the left eye. Multimodal imaging showed macular atrophy in the right eye with speckled hypoautofluorescence of the described lesions. Genetic testing showed a homozygous splice acceptor variant of the ATP6V0A2 gene. The natural history of the presented pigmentary lesions is not known, and further follow-up is needed to assess any progressive nature. Our case adds to the variability of ophthalmic manifestations reported in autosomal recessive cutis laxa type 2A and, therefore, to the importance of regular ophthalmic surveillance in patients with cutis laxa.

Cutis laxa (CL) can be caused by mutations in a number of genes. Cutis laxa with autosomal recessive inheritance due to mutations in several genes, including mutations in the ATP6V0A2 gene, causes autosomal recessive cutis laxa type 2A (ARCL2A). The ATP6V0A2 gene encodes the a2 subunit in the V-ATPases pump. The V-ATPases are located in the membrane of some organelles, including the Golgi or some vesicles, and act as ATP-dependent proton pumps to pH adjustment intracellular segments. Mutations in the ATP6V0A2 gene consist present in ARCL2A patients. We present the case of a 12-year-old girl who was referred to Rasad Laboratory (Tehran, Iran) at the age of 5 with a set of symptoms of congenital disorders. Her clinical phenotype contains distal symmetrical sensory and motor polyneuropathy, loose joints, large nasal roots, growth delay, and wrinkled skin. Also, there was a history of the parental marriage of consanguinity. A potentially pathogenic homozygous deletion mutation was detected in the ATP6V0A2 gene related to ARCL2A. This mutation has not been reported in the other patients with ARCL2A. A novel homozygous deletion mutation in ATP6V0A2 is supposed to be the reason for disease in our proband.

Autosomal recessive cutis laxa type 2A (ARCL2A; OMIM: 219200) is characterized by neurovegetative, developmental and progeroid elastic skin anomalies. It is caused by biallelic variation in ATPase, H+ transporting V0 subunit A2 (ATP6V0A2; OMIM: 611716) located on chromosome 12q24.31. Autosomal recessive cutis laxa type 3A (ARCL3A; OMIM: 219150) is another subclinical type characterized by short stature, ophthalmological abnormalities and a progeria-like appearance. The ARCL3A is caused by loss of function alterations in the aldehyde dehydrogenase 18 family member A1 (ALDH18A1; OMIM: 138250) gene located at chromosome 10q24.1. Whole-exome sequencing (WES), and Sanger sequencing were performed for molecular diagnosis. 3D protein modeling was performed to investigate the deleterious effect of the variant on protein structure. In this study, clinical and molecular diagnosis were performed for two families, ED-01 and DWF-41, which displayed hallmark features of ARCL2A and ARCL3A, respectively. Three affected individuals in the ED-01 family (IV-4, IV-5 and V-3) displayed sagging loose skin, down-slanting palpebral fissures, excessive wrinkles on the abdomen, hands and feet, and prominent veins on the trunk. Meanwhile the affected individuals in the DWF-41 family (V-2 and V-3) had progeroid skin, short stature, dysmorphology, low muscle tone, epilepsy, lordosis, scoliosis, delayed puberty and internal genitalia. WES in the index patient (ED-01: IV-4) identified a novel homozygous deletion (NM_012463.3: c.1977_1980del; p.[Val660LeufsTer23]) in exon 16 of the ATP6V0A2 while in DWF-41 a novel homozygous missense variant (NM_001323413.1:c.1867G>A; p.[Asp623Asn]) in exon 15 of the ALDH18A1 was identified. Sanger validation in all available family members confirmed the autosomal recessive modes of inheritances in each family. Three dimensional in-silico protein modeling suggested deleterious impact of the identified variants. Furthermore, these variants were assigned class 1 or "pathogenic" as per guidelines of American College of Medical Genetics 2015. Screening of ethnically matched healthy controls (n = 200 chromosomes), excluded the presence of these variations in general population. To the best of our knowledge, this is the first report of ATP6V0A2 and ALDH18A1 variations in the Pakhtun ethnicity of Pakistani population. The study confirms that WES can be used as a first-line diagnostic test in patients with cutis laxa, and provides basis for population screening and premarital testing to reduce the diseases burden in future generations. ATP6V0A2-related cutis laxa is characterized by generalized cutis laxa, findings associated with generalized connective tissue disorder, developmental delays, and a variety of neurologic findings including abnormality on brain MRI. At birth, hypotonia, overfolded skin, and distinctive facial features are present and enlarged fontanelles are often observed. During childhood, the characteristic facial features and thick or coarse hair may become quite pronounced. The skin findings decrease with age, although easy bruising and Ehlers-Danlos-like scars have been described in some. In most (not all) affected individuals, cortical and cerebellar malformations are observed on brain MRI. Nearly all affected individuals have developmental delays, seizures, and neurologic regression. The diagnosis of ATP6V0A2-related cutis laxa is established by the presence of suggestive findings and biallelic pathogenic variants in ATP6V0A2 identified by molecular genetic testing. Treatment of manifestations: Standard treatment for congenital hip dislocation, inguinal hernias, high myopia, and seizure disorders. Early intervention and management of developmental delays and intellectual disability and psychological help as needed for self-image issues. Surveillance: Annual ophthalmologic examination, EEG, and monitoring of anticonvulsive drug levels. ATP6V0A2-related cutis laxa is inherited in an autosomal recessive manner. If both parents are known to be heterozygous for an ATP6V0A2 pathogenic variant, each sib of an affected individual has at conception a 25% chance of being affected, a 50% chance of being an asymptomatic carrier, and a 25% chance of being unaffected and not a carrier. Once the ATP6V0A2 pathogenic variants have been identified in an affected family member, carrier testing for at-risk relatives, prenatal testing for a pregnancy at increased risk, and preimplantation genetic testing for ATP6V0A2-related cutis laxa are possible.

ATP6V0A2-related cutis laxa, also known as autosomal recessive cutis laxa type 2A (ARCL2A), is a subtype of hereditary cutis laxa originally characterized by skin, skeletal, and neurological involvement, and a combined defect of N-glycosylation and O-glycosylation. The associated clinical spectrum subsequently expanded to a less severe phenotype dominated by cutaneous involvement. At the moment, ARCL2A was described in a few case reports and series only. An Italian adult woman ARCL2A with a phenotype restricted to skin and the two novel c.3G>C and c.1101dup ATP6V0A2 variants has been reported. A systematic literature review allowed us to identify 69 additional individuals from 64 families. Available data were scrutinized in order to describe the clinical and molecular variability of ARCL2A. About 78.3% of known variants were predicted null alleles, while 11 were missense and 2 affected noncanonical splice sites. Age at ascertainment appeared as the unique phenotypic discriminator with earlier age more commonly associated with facial dysmorphism (p .02), high/cleft palate (p .005), intellectual disability/global developmental delay (p .013), and seizures (p .024). No specific genotype-phenotype correlations were identified. This work confirmed the existence of an attenuated phenotype associated with ATP6V0A2 biallelic variants and offers an updated critique to the clinical and molecular variability of ARCL2A.

OBJECTIVE To identify potential mutation in a patient with cutis laxa through exome sequencing of genetic disease-related genes and explore its clinical and genetic features. METHODS Clinical data was collected for the proband and her parents. Exome sequencing was carried out on the proband. Suspected mutations were verified by Sanger sequencing. RESULTS Exome sequencing identified a compound heterozygous mutation of the ATP6V0A2 gene, c.187C>T (p.R63X) and c.1189G>C (p.A397P), in the proband. The mutations were respectively inherited from the father and mother. The patient was diagnosed with autosomal recessive cutis laxa type 2A (ARCL2A). CONCLUSION A case with ARCL2A was diagnosed. The novel mutation has expanded the spectrum of ATP6V0A2 mutations. Exome sequencing is a useful tool for the diagnosis of complex genetic diseases.