STAC3 related congenital myopathy: A case series of seven Comorian patients.

The Bailey-Bloch congenital myopathy, also known as Native American myopathy (NAM), is an autosomal recessive congenital myopathy first reported in the Lumbee tribe people settled in North Carolina (USA), and characterized by congenital weakness and arthrogryposis, cleft palate, ptosis, short stature, kyphoscoliosis, talipes deformities, and susceptibility to malignant hyperthermia (MH) triggered by anesthesia. NAM is linked to STAC3 gene coding for a component of excitation-contraction coupling in skeletal muscles. A homozygous missense variant (c.851G > C; p.Trp284Ser) in STAC3 segregated with NAM in the Lumbee families. Non-Native American patients with STAC3 related congenital myopathy, and with other various variants of STAC3 have been reported. Here, we present seven patients from the Comoros Islands (located in the Mozambique Channel) diagnosed with STAC3 related congenital myopathy and having the recurrent variant identified in the Lumbee people. The series is the second largest series of patients having STAC3 related congenital myopathy with a shared ethnicity after le Lumbee series. Local history and geography may explain the overrepresentation of NAM in the Comorian Archipelago with a founder effect. Further researches would be necessary for the understanding of the onset of the NAM in Comorian population as search of the "classical" STAC3 variant in East African population, and haplotypes comparison between Comorian and Lumbee patients.

A prospective study evaluating congenital CMV infection in Mayotte and La Reunion Islands (France).

OBJECTIVES Congenital cytomegalovirus infection (cCMV) affects around 3400 newborns each year in France, of whom 700 will develop sequelae, primarily sensorineural hearing loss. Our objectives were (1) to evaluate incidence of cCMV in two French departments located in the Indian Ocean: Mayotte and La Reunion, and (2) evaluate interest and feasibility/acceptability of universal screening of cCMV at birth. MATERIAL AND METHODS We implemented a universal neonatal CMV screening in Mayotte during 7 months in 2019 and in La Reunion during one month in March 2020. Saliva swabs were collected in the first three days of life, and tested for CMV DNA by PCR. A short survey allowed evaluating whether this screening is acceptable and feasible. RESULTS: A total of 1026 newborns were screened: 854 in Mayotte and 172 in La Reunion. In Mayotte, cCMV incidence was evaluated at a minimum of 1.6 % (95 % CI 0.94-2.81). In La Reunion, cCMV incidence was evaluated at a minimum of 1.2 % (95 % CI -0.20-4.57). All cCMV infants were born to mothers with non-primary CMV infection. Only 0.7 % parents refused the screening. CONCLUSIONS cCMV incidence in Mayotte and La Reunion is higher than in metropolitan France. This diagnosis should not be overlooked, especially since the time dedicated to screening and its feeling by the parents seem to be acceptable.