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Recent advances in molecular genetics have allowed the determination of the genetic cause of some childhood non-syndromic deafness. In Portugal only a small proportion of families are referred to a clinical genetics service in order to clarify the etiology of the deafness and to provide genetic counseling. Consequently, there are no published studies of the prior beliefs of parents about the causes of hereditary deafness of their children and their genetic knowledge after receipt of genetic counseling. In order to evaluate the impact of genetic counseling, 44 parents of 24 children with the diagnosis of non-syndromic sensorineural prelingual deafness due to mutations in the GJB2 (connexin 26), completed surveys before and after genetic counseling. Before counseling 13.6 % of the parents knew the cause of deafness; at a post-counseling setting this percentage was significantly higher, with 84.1 % of the parents accurately identifying the etiology. No significant differences were found between the answers of mothers and fathers either before or after genetic counseling. Parents' level of education was a significant factor in pre-test knowledge. After genetic counseling 95.5 % of the parents stated that the consultation had met their expectations, 70.5 % remembered correctly the inheritance pattern, and 93.2 % correctly recalled the chance of risk of deafness. These results underline the importance of genetic counseling in demystifying parents' beliefs about the etiology of their children's deafness.

Objective: Genetic counseling and carrier screening are part of the gamete donation process by healthy individuals. We aim to review the findings of genetic counseling and carrier screening of a cohort of candidates at our public gametes bank.Methods: Thirty-four male and 64 female candidates had genetic counseling with a medical geneticist before donation. Of these, one female candidate voluntarily dropped-out. Thirty-four males and 63 females performed karyotype and screening for the more common pathogenic variants for CFTR-related cystic fibrosis and spinal muscular atrophy (SMN1) in the Portuguese population. In addition, all females also performed Fragile X expansion screening (FMR1). Thirty candidates with known or assumed African ancestry performed hemoglobinopathies screening.Results: Six candidates were definitely or temporarily withheld from the donation process given their family or personal history that required further investigation. Of 97 candidates tested, 16.5% presented anomalous laboratory results (16/97): ten candidates were carriers for an autosomal recessive disorder -cystic fibrosis (5/97), sickle cell anemia (3/30), and spinal muscular atrophy (2/97). One female was an FMR1 pre-mutation carrier (1/63). One female candidate presented with triple X mosaicism: 47,XXX[2]/46,XX [50]. Two candidates presented with chromosomal instability of unknown origin. In one candidate, a mosaic for the Philadelphia chromosome was detected, revealing the diagnosis of chronic myeloid leukemia.Conclusions: From a cohort of 97 candidates, 21.7% had a family/personal history or an anomalous laboratory result that required additional genetic counseling, stressing the importance of performing pre-donation genetic counseling in this population.

Mohr-Tranebjaerg syndrome (MTS) is an X-linked recessive disorder caused by TIMM8A loss of function. It is characterized by sensorineural hearing loss in childhood, progressive optic atrophy in early adulthood, early onset dementia and psychiatric symptoms of variable expressivity. We present a family with 4 affected males, explore age-related and interfamilial variability and review the literature.Case reportA 31 years-old male developed psychiatric symptoms at age 18 and presented early onset dementia. Sensorineural hearing loss had been diagnosed in childhood. At 28yo, he developed dysarthria, dysphonia, dysmetria, limb hyperreflexia, dystonia, and spasticity following an acute encephalopathic crisis. WES revealed a hemizygous novel likely pathogenic variant in TIMM8A, c.45_61dup p.(His21Argfs*11), establishing the diagnosis of MTS. Genetic counseling of the family allowed the diagnosis of three other symptomatic relatives −3 nephews (11yo and two 6yo twins), children of a carrier sister. The oldest nephew had been followed since 4yo due to speech delay. Sensorineural hearing loss was diagnosed at 9yo, and hearing aids were prescribed. The two other nephews were monozygotic twins, and both had unilateral strabismus. One of the twins had macrocephaly and hypoplasia of the anterior temporal lobe, as disclosed by an MRI performed due to febrile seizures. Both had developmental delays, with the language being the most affected area. Their audiograms confirmed hearing loss. All three nephews were hemizygous for the familial TIMM8A variant.DiscussionHearing loss, an early sign of MTS due to auditory neuropathy, can often be overlooked until more severe features of the disorder manifest. Recurrence risk is high for female carriers, and reproductive options should be offered. Early monitoring of hearing and vision loss and neurological impairment in MTS patients is mandatory since early interventions may positively impact their development. This family showcases the importance of performing a timely etiological investigation of hearing loss and its impact on genetic counseling.

Background The aging process is characterized by a gradual impairment of several capacities, such as hearing, memory and communication, which implies changes at various levels and, consequently, changes in both hearing and auditory skills, of which the auditory temporal ordering is an example. Methods The sample consisted of 23 elderly individuals, aged between 70 and 96 years (average of 83.09 years) and with mild to severe type I sensorineural hearing loss. For the collection of information, the pure tone audiogram, the frequency and duration pattern tests, the verbal and non-verbal sequential memory tests were used. Results The results revealed that between age and the auditory temporal order tests there was a negative correlation (except in the duration pattern test in the left ear) and between the auditory threshold and the auditory temporal order tests there was negative correlation (except in the duration pattern test in the right ear). Conclusions It is concluded that in this sample the ability of auditory temporal ordering was influenced by aging and hearing loss, which shows that as the age of the elderly progresses and the degree of hearing loss increases the difficulties in temporal auditory processing become larger. This leads us to consider that these elderly have several difficulties in temporal auditory processing and that an intervention as auditory training may be advantageous for the elderly, as it could improve their central auditory processing and, consequently, their hearing, memory and quality of life.