Hereditary Split-hand and Split-foot in a family

A family from an Andhra district visited us for genetic counseling with their 1-year-old baby boy who was reportedly healthy, active and happy. His hands were covered in mittens, and feet in yellow socks. His parents expressed concern about his future health, and the chance of having another baby with the condition they had chosen to hide with socks and mittens-  two fused (joined) fingers on the right hand, and only two large toes on both feet – a condition commonly referred to as “Split Hand/Foot”. He was unable to walk properly because of his feet; doctors had offered plastic surgery to help the feet and hand appear ‘normal’. They had positive family history (affected niece and nephew), were informed of its hereditary nature, and believed every future child would have the same condition. Luckily, a pediatrician from their district referred them to us at MapmyGenome for genetic counseling.

As the appointment progressed, it was clear they came in with two major misconceptions:

1. They had, assuming a 100% recurrence risk, planned on not having any more children, and;

2. They thought their baby’s mental development would be affected. It is extremely common for families to have misinformation about the nature, cause, or recurrence of a genetic condition, and this is often a source of parental anxiety and distress.

Genetic Counseling is aimed at addressing such concerns

This is exactly what we did. Here is how:

• Nature of the condition:

  A common anxiety most parents in their situation have is the deterioration of health. While some genetic conditions are progressive, have multiple organ involvement, and affect physical/mental development, this is not the case for Split Hand/Foot. The couple was reassured that the baby would most likely have normal physical and mental development, and be able to lead a reasonably normal life. Plastic surgery and special shoes would help the appearance and mobility.

• Cause:

  Parents may often have false/incorrect beliefs surrounding causation. It is important to address these misconceptions, educate families and discuss available testing options to confirm the genetic cause. Confirming a genetic cause is crucial not only for appropriate clinical management, but also to provide accurate recurrence risk to the couple and other at-risk family members. In this case, genetic testing in the baby revealed a change in both copies of the WTNT10B gene (we all have 2 copies of each gene- one inherited from our mother and the other, from our father).

• Recurrence:

  For this family, since genetic testing revealed a homozygous (in both copies of the gene) mutation in the son, it meant both parents were obligate, unaffected carriers (in a single copy of the gene) of the same mutation, and now aware of their carrier status. This information revised their perceived risk from 100% to 25% (1 in 4 chance), and changed their minds about not having another baby.

A recommendation to offer prenatal testing during a future pregnancy was made, they were encouraged to come back for a prenatal genetic counseling during their next pregnancy, and a detailed summary letter with recommendations was sent to the referring pediatrician back in their district. We hope to see them again when they are pregnant, and to help them make the right decision for themselves.

This case is important because not every village, district, or state in India has an expert in genetics; a referral to genetic counseling can be life changing for several families such as this. This family was able to have their misinformation corrected, concerns addressed, and be helped and empowered.

About the Author

The writer, Dr. Risha Nahar Lulla, MSc (Glasgow, UK), Ph.D. (Delhi, India) has over 10 years of experience in the field of medical genetics. She is a practicing ‘Board-Certified Senior Genetic Counselor’ at MapmyGenome India Ltd, based in Hyderabad, India (previous experience at KIMS hospitals, Hyderabad and Sir Ganga Ram Hospital, Delhi). She has counseled thousands of families with various genetic conditions, including children with inborn errors of metabolism, muscular dystrophy, and congenital malformations; adults with neurodegenerative diseases, ataxia, and familial cancers. She has published several research papers in renowned scientific journals and has been featured in several daily national newspapers for her commendable contribution in the niche field of medical genetics. Her main interests lie in ‘preventative genetics’ that involves pre-marital, pre-conception and prenatal genetic testing and counseling for couples and newborns. She is also involved in voluntary work where she conducts genetic awareness programs to spread awareness about the importance of screening and prevention of common genetic disorders in India.