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BackgroundSex determining factor (SRY) located on the short arm of the Y chromosome, plays an important role in initiating male sex determination, resulting in development of testicular tissue. Presence of the SRY gene in females results in XY sex reversal and increased risk of gonadal germ cell tumours if the karyotype also includes the so-called GonadoBlastoma on the Y chromosome (GBY) region. The majority of mutations within the SRY gene are de novo affecting only a single individual in the family. The mutations within the high-mobility group (HMG) region have the potential to affect its DNA binding activity.Case PresentationWe performed G- and R-banding cytogenetic analysis of the patient and her family members including her father. We also performed molecular genetic analysis of SRY gene. Cytogenetic analysis in the patient (Turner Syndrome) revealed the mosaic karyotype as 45, X/46, XY (79%/21% respectively) while her father (milder features with testicular dysgenesis syndrome) has a normal male karyotype (46, XY). Using molecular approach, we screened the patient and her father for mutations in the SRY gene. Both patient and her father showed the same deletion of cytosine within HMG box resulting in frame shift mutation (L94fsX180), the father in a mosaic pattern. Histological examination of the gonads from the patient revealed the presence of gonadoblastoma formation, while the father presented with oligoasthenozoospermia and a testicular seminoma. The frameshift mutation at this codon is novel, and may result in a mutated SRY protein.ConclusionOur results suggest that lack of a second sex chromosome in majority cells of the patient may have triggered the short stature and primary infertility, and the mutated SRY protein may be associated with the development of gonadoblastoma. It is of importance to note that mosaic patients without a SRY mutation also have a risk for malignant germ cell tumors.

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System-assigned random passwords offer security guarantees against guessing attacks but suffer from poor memorability. In this work, we review the cognitive psychology literature and identify two training methods appropriate to aid users in memorizing system-assigned passwords. The method of loci exploits users' spatial and visual memory, while the link method helps users by creating a chain of memory cues. We developed techniques to automatically take a given random password and generate training aids (videos) based on each of these methods. The results of a memorability study showed that both methods were significantly better than a control condition (no training) and that the method of loci had a login success rate of 86%, a high value for any recall-based study with system-assigned passwords. With a registration time of 160 seconds and a median login time of 9 seconds, this method holds promise as a direction to addressing the usability-security trade-off in user authentication. We further extend this idea to help users memorize long system-assigned random passwords that offer almost crypto-level security and conduct a second memorability study. The results of this study demonstrated that with the help of a password hint, 81% of participants were able to recall the password after a week. This indicates that the method of loci can be leveraged to help users memorize cryptographically-strong secret in just one session, and thus offers a more viable alternative to the spaced repetition technique, which involves dozens of sessions of user training. Permission to freely reproduce all or part of this paper for noncommercial purposes is granted provided that copies bear this notice and the full citation on the first page. Reproduction for commercial purposes is strictly prohibited without the prior written consent of the Internet Society, the first-named author (for reproduction of an entire paper only), and the author's employer if the paper was prepared within the scope of employment.