Global Journal of Medical Research, E: Gynecology and Obstetrics, Volume 21 Issue 3

30 Year 2021 Global Journal of Medical Research Volume XXI Issue III Version I ( DD ) E © 2021 Global Journals Pregnancy in a Patient with RETT SYNDROME Mutation: Dilemmas in Management However, it could also be related to germline mosaicism. The gene could also be transmitted vertically from asymptomatic carrier mothers. With carrier mothers, there is a 50% risk that the offsprings can be affected. The mothers may be asymptomatic carriers because of favorable skewing of x chromosome inactivation, and hence they do not have the typical features. Variable X inactivation can lead to different phenotypes-healthy carrier females to mild and severely affected females and severe congenital encephalopathy in males despite having the same mutation. X inactivation studies may not be very reliable in predicting the disease severity [4]. Carrier mothers with favorable skewing may have minimal to no clinical abnormalities like our patient. However, it is difficult to predict the outcome of this baby who needs close monitoring. Recurrence, as discussed earlier, can be due to asymptomatic nonpenetrant carrier mothers or to parental germinal mosaicism for the MECP2 mutation. Since germline mosaicism can neither be predicted nor detected, families with one affected patient can benefit from prenatal diagnosis. IV. C onclusion It is important to think of possible genetic inheritances in patients with a strong family history of developmental problems and consanguinity. Genetic counseling and discussion of reproductive choices in carrier couples, including prenatal diagnosis and preimplantation testing, help to prevent recurrence in future pregnancies. Informed consent: The authors thank the patient for her consent to publish this case. Author contribution: Srimathy Raman was responsible for the content of the manuscript. The other authors supervised the drafting and editing of the manuscript. Conflict of interest: The case was presented as a poster in Karnataka State Obs and Gyn Association meeting, Shimoga, Karnataka, 2017, and CUSP Conference, Chennai 2018. There are no other conflicts of interest to declare. R eferences R éférences R eferencias 1. Hagberg B. Rett's syndrome: Prevalence and impact on progressive severe mental retardationin girls. Acta Paediatr Scand .1985; 74:405–408. 2. Amir RE, Van den Veyver IB, Wan M, TranCQ, Franke U, Zoghbi HY. Rett syndrome is caused by mutations in X-linked MECP2 , encoding methyl- CpG-binding protein 2. Nat Genet . 1999; 23: 185–188. 3. Armstrong J, Aibar E, Pineda M et. al. Prenatal Diagnosis in Rett Syndrome. Med Genet . 2006; 43: 814–816. doi: 10.1136/jmg.2006.042077. 4. Huppke P, MaierEM, Warnke A, Brendel C, Laccone F, Gartner J. Very mild cases of Rett syndrome with skewed X inactivation. Fetal Diagn Ther. 2002; 17:200–204. Table 1: Exome sequencing analysis result Patient ID Zygosity Exon # Chromosomal Coordinates HGVS Nomenclature Amino Acid change Carrier Status Mother X Heterozygous 3 chrx:153296711 NM_001110792.1 p.Arg202Cys Obligate Carrier Father Y Homozygous (wild type) 3 chrx:153296711 NM_001110792.1 p.Arg202Cys Normal (Wild type) Child A Heterozygous 3 chrx:153296711 NM_001110792.1 p.Arg202Cys Affected Child B Heterozygous 3 chrx:153296711 NM_001110792.1 p.Arg202Cys Affected Amniotic Fluid-Fetus Heterozygous 3 chrx:153296711 NM_001110792.1 p.Arg202Cys ? Carrier/ ?Affected